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1.
Nature ; 634(8032): 69-73, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39294380

RESUMO

Studies of moiré systems have explained the effect of superlattice modulations on their properties, demonstrating new correlated phases1. However, most experimental studies have focused on a few layers in two-dimensional systems. Extending twistronics to three dimensions, in which the twist extends into the third dimension, remains underexplored because of the challenges associated with the manual stacking of layers. Here we study three-dimensional twistronics using a self-assembled twisted spiral superlattice of multilayered WS2. Our findings show an opto-twistronic Hall effect driven by structural chirality and coherence length, modulated by the moiré potential of the spiral superlattice. This is an experimental manifestation of the noncommutative geometry of the system. We observe enhanced light-matter interactions and an altered dependence of the Hall coefficient on photon momentum. Our model suggests contributions from higher-order quantum geometric quantities to this observation, providing opportunities for designing quantum-materials-based optoelectronic lattices with large nonlinearities.

2.
Nat Mater ; 23(3): 323-330, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38191631

RESUMO

Moiré superlattices formed by twisting trilayers of graphene are a useful model for studying correlated electron behaviour and offer several advantages over their formative bilayer analogues, including a more diverse collection of correlated phases and more robust superconductivity. Spontaneous structural relaxation alters the behaviour of moiré superlattices considerably and has been suggested to play an important role in the relative stability of superconductivity in trilayers. Here we use an interferometric four-dimensional scanning transmission electron microscopy approach to directly probe the local graphene layer alignment over a wide range of trilayer graphene structures. Our results inform a thorough understanding of how reconstruction modulates the local lattice symmetries crucial for establishing correlated phases in twisted graphene trilayers, evincing a relaxed structure that is markedly different from that proposed previously.

3.
Plant Physiol ; 196(2): 948-960, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38888990

RESUMO

Grain size is one of the most important traits determining crop yield. However, the mechanism controlling grain size remains unclear. Here, we confirmed the E3 ligase activity of DECREASED GRAIN SIZE 1 (DGS1) in positive regulation of grain size in rice (Oryza sativa) suggested in a previous study. Rice G-protein subunit gamma 2 (RGG2), which negatively regulates grain size, was identified as an interacting protein of DGS1. Biochemical analysis suggested that DGS1 specifically interacts with canonical Gγ subunits (rice G-protein subunit gamma 1 [RGG1] and rice G-protein subunit gamma 2 [RGG2]) rather than non-canonical Gγ subunits (DENSE AND ERECT PANICLE 1 [DEP1], rice G-protein gamma subunit type C 2 [GCC2], GRAIN SIZE 3 [GS3]). We also identified the necessary domains for interaction between DGS1 and RGG2. As an E3 ligase, DGS1 ubiquitinated and degraded RGG2 via a proteasome pathway in several experiments. DGS1 also ubiquitinated RGG2 by its K140, K145, and S147 residues. Thus, this work identified a substrate of the E3 ligase DGS1 and elucidated the post-transcriptional regulatory mechanism of the G-protein signaling pathway in the control of grain size.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Ubiquitina-Proteína Ligases , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/enzimologia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/genética , Grão Comestível/metabolismo , Ubiquitinação , Plantas Geneticamente Modificadas , Proteólise , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Sementes/genética , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/genética
4.
Nano Lett ; 24(40): 12508-12514, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39316821

RESUMO

Electron collimation via a graphene p-n junction allows electrostatic control of ballistic electron trajectories akin to that of an optical circuit. Similar manipulation of novel correlated electronic phases in twisted-bilayer graphene (tBLG) can provide additional probes to the underlying physics and device components toward advanced quantum electronics. In this work, we demonstrate collimation of the electron flow via gate-defined moiré barriers in a tBLG device, utilizing the band-insulator gap of the moiré superlattice. A single junction can be tuned to host a chosen combination of conventional pseudo barrier and moiré tunnel barriers, from which we demonstrate improved collimation efficiency. By measuring transport through two consecutive moiré collimators separated by 1 µm, we demonstrate evidence of electron collimation in tBLG in the presence of realistic twist-angle inhomogeneity.

5.
BMC Genomics ; 25(1): 230, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429690

RESUMO

BACKGROUND: Krüppel-like factor 1 (KLF1), a crucial erythroid transcription factor, plays a significant role in various erythroid changes and haemolytic diseases. The rare erythrocyte Lutheran inhibitor (In(Lu)) blood group phenotype serves as an effective model for identifying KLF1 hypomorphic and loss-of-function variants. In this study, we aimed to analyse the genetic background of the In(Lu) phenotype in a population-based sample group by high-throughput technologies to find potentially clinically significant KLF1 variants. RESULTS: We included 62 samples with In(Lu) phenotype, screened from over 300,000 Chinese blood donors. Among them, 36 samples were sequenced using targeted Next Generation Sequencing (NGS), whereas 19 samples were sequenced using High Fidelity (HiFi) technology. In addition, seven samples were simply sequenced using Sanger sequencing. A total of 29 hypomorphic or loss-of-function variants of KLF1 were identified, 21 of which were newly discovered. All new variants discovered by targeted NGS or HiFi sequencing were validated through Sanger sequencing, and the obtained results were found to be consistent. The KLF1 haplotypes of all new variants were further confirmed using clone sequencing or HiFi sequencing. The lack of functional KLF1 variants detected in the four samples indicates the presence of additional regulatory mechanisms. In addition, some samples exhibited BCAM polymorphisms, which encodes antigens of the Lutheran (LU) blood group system. However, no BCAM mutations which leads to the absence of LU proteins were detected. CONCLUSIONS: High-throughput sequencing methods, particularly HiFi sequencing, were introduced for the first time into genetic analysis of the In(Lu) phenotype. Targeted NGS and HiFi sequencing demonstrated the accuracy of the results, providing additional advantages such as simultaneous analysis of other blood group genes and clarification of haplotypes. Using the In(Lu) phenotype, a powerful model for identifying hypomorphic or loss-of-function KLF1 variants, numerous novel variants have been detected, which have contributed to the comprehensive understanding of KLF1. These clinically significant KLF1 mutations can serve as a valuable reference for the diagnosis of related blood cell diseases.


Assuntos
Antígenos de Grupos Sanguíneos , Fatores de Transcrição Kruppel-Like , Antígenos de Grupos Sanguíneos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Sistema do Grupo Sanguíneo Lutheran/genética , Mutação , Humanos
6.
J Am Chem Soc ; 146(23): 16105-16111, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38829312

RESUMO

In this work, we develop a twist-dependent electrochemical activity map, combining a low-energy continuum electronic structure model with modified Marcus-Hush-Chidsey kinetics in trilayer graphene. We identify a counterintuitive rate enhancement region spanning the magic angle curve and incommensurate twists in the system geometry. We find a broad activity peak with a ruthenium hexamine redox couple in regions corresponding to both magic angles and incommensurate angles, a result qualitatively distinct from the twisted bilayer case. Flat bands and incommensurability offer new avenues for reaction rate enhancements in electrochemical transformations.

7.
Electrophoresis ; 45(5-6): 548-556, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38185764

RESUMO

Several molecular biology methods are available for high-throughput blood typing. In this study, we aimed to build a high-throughput blood-group genetic screening system for high-frequency blood-group antigen-negative rare-blood groups in donors and patients. The amplification primers for all blood-type gene fragments involving the selected alleles were designed for detection. Single-base extend primers were also designed based on specific loci. DNA fragments were detected by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MS) for the last nucleotide identification of amplification products in the extend step. The accuracy was verified by known samples. Thirty-six random samples were detected by serological tests and sequencing to verify the system stability. After verification, according to the collected known rare-blood-type samples, all the alleles designed to be detected matched with the validated single-nucleotide polymorphisms. The verification tests showed that all genotyping results of the random samples were in accordance with the findings of serotyping and sequencing. Then, 1258 random donor samples were screened by the built typing system after the verification. Three Fy(a-) and four s- were screened out in 1258 random blood samples. The multiple polymerase chain reaction-based MS detection system can be used in rare-blood-type screening with good accuracy and stability.


Assuntos
Antígenos de Grupos Sanguíneos , Humanos , Antígenos de Grupos Sanguíneos/genética , Genótipo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Alelos , Polimorfismo de Nucleotídeo Único , Primers do DNA/genética
8.
BMC Cancer ; 24(1): 1199, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39342165

RESUMO

BACKGROUND: Colorectal cancer, a prevalent malignancy worldwide, poses a significant challenge due to the lack of effective prognostic tools. In this study, we aimed to develop a functional gene signature to stratify colorectal cancer patients into different groups with distinct characteristics, which will greatly facilitate disease prediction. RESULTS: Patients were stratified into high- and low-risk groups using a prediction model built based on the functional gene signature. This innovative approach not only predicts clinicopathological features but also reveals tumor immune microenvironment types and responses to immunotherapy. The study reveals that patients in the high-risk group exhibit poorer pathological features, including invasion depth, lymph node metastasis, and distant metastasis, as well as unfavorable survival outcomes in terms of overall survival and disease-free survival. The underlying mechanisms for these observations are attributed to upregulated tumor-related signaling pathways, increased infiltration of pro-tumor immune cells, decreased infiltration of anti-tumor immune cells, and a lower tumor mutation burden. Consequently, patients in the high-risk group exhibit a diminished response to immunotherapy. Furthermore, the high-risk group demonstrates enrichment in extracellular matrix-related functions and significant infiltration of cancer-associated fibroblasts (CAFs). Single-cell transcriptional data analysis identifies CAFs as the primary cellular type expressing hub genes, namely ACTA2, TPM2, MYL9, and TAGLN. This finding is further validated through multiple approaches, including multiplex immunohistochemistry (mIHC), polymerase chain reaction (PCR), and western blot analysis. Notably, TPM2 emerges as a potential biomarker for identifying CAFs in colorectal cancer, distinguishing them from both colorectal cancer cell lines and normal colon epithelial cell lines. Co-culture of CAFs and colorectal cancer cells revealed that CAFs could enhance the tumorigenic biofunctions of cancer cells indirectly, which could be partially inhibited by knocking down CAF original TPM2 expression. CONCLUSIONS: This study introduces a functional gene signature that effectively and reliably predicts clinicopathological features and the tumor immune microenvironment in colorectal cancer. Moreover, the identification of TPM2 as a potential biomarker for CAFs holds promising implications for future research and clinical applications in the field of colorectal cancer.


Assuntos
Neoplasias Colorretais , Microambiente Tumoral , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/imunologia , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Prognóstico , Feminino , Perfilação da Expressão Gênica , Masculino , Transcriptoma , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/imunologia , Fibroblastos Associados a Câncer/patologia
9.
J Magn Reson Imaging ; 60(5): 1867-1879, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38308397

RESUMO

BACKGROUND: Multiple sclerosis (MS) lesion evolution may involve changes in diamagnetic myelin and paramagnetic iron. Conventional quantitative susceptibility mapping (QSM) can provide net susceptibility distribution, but not the discrete paramagnetic and diamagnetic components. PURPOSE: To apply susceptibility separation (χ separation) to follow lesion evolution in MS with comparison to R2*/R2 '/QSM. STUDY TYPE: Longitudinal, prospective. SUBJECTS: Twenty relapsing-remitting MS subjects (mean age: 42.5 ± 9.4 years, 13 females; mean years of symptoms: 4.3 ± 1.4 years). FIELD STRENGTH/SEQUENCE: Three-dimensional multiple echo gradient echo (QSM and R2* mapping), two-dimensional dual echo fast spin echo (R2 mapping), T2-weighted fluid attenuated inversion recovery, and T1-weighted magnetization prepared gradient echo sequences at 3 T. ASSESSMENT: Data were analyzed from two scans separated by a mean interval of 14.4 ± 2.0 months. White matter lesions on fluid-attenuated inversion recovery were defined by an automatic pipeline, then manually refined (by ZZ/AHW, 3/25 years' experience in MRI), and verified by a radiologist (MN, 25 years' experience in MS). Susceptibility separation yielded the paramagnetic and diamagnetic susceptibility content of each voxel. Lesions were classified into four groups based on the variation of QSM/R2* or separated into positive/negative components from χ separation. STATISTICAL TESTS: Two-sample paired t tests for assessment of longitudinal differences. Spearman correlation coefficients to assess associations between χ separation and R2*/R2 '/QSM. Significant level: P < 0.005. RESULTS: A total of 183 lesions were quantified. Categorizing lesions into groups based on χ separation demonstrated significant annual changes in QSM//R2*/R2 '. When lesions were grouped based on changes in QSM and R2*, both changing in unison yielded a significant dominant paramagnetic variation and both opposing yielded a dominant diamagnetic variation. Significant Spearman correlation coefficients were found between susceptibility-sensitive MRI indices and χ separation. DATA CONCLUSION: Susceptibility separation changes in MS lesions may distinguish and quantify paramagnetic and diamagnetic evolution, potentially providing additional insight compared to R2* and QSM alone. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.


Assuntos
Imageamento por Ressonância Magnética , Esclerose Múltipla Recidivante-Remitente , Humanos , Feminino , Masculino , Adulto , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Estudos Prospectivos , Pessoa de Meia-Idade , Estudos Longitudinais , Reprodutibilidade dos Testes , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Processamento de Imagem Assistida por Computador/métodos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
10.
Anticancer Drugs ; 35(9): 817-829, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39018257

RESUMO

Cervical cancer is among the most common gynecological malignancies. G protein-coupled estrogen receptor (GPER) is involved in the development of various tumors; however, its role in cervical cancer remains unclear. We investigated whether G15, an inhibitor of GPER, can regulate its expression and affect cervical cancer progression. We examined the biological behaviors of G15-treated SiHa and HeLa cells using Cell Counting Kit-8, monoclonal proliferation, plate scratching, and Transwell invasion experiments. Western blotting was used to detect the expression of GPER, E-cadherin, N-cadherin, vimentin, Bcl-2, Bax, phosphatidylinositol-3-kinase (PI3K)/AKT, and programmed death ligand 1 (PD-L1). The expression of GPER, E-cadherin, vimentin, and PD-L1 in cervical cancer and adjacent tissues was detected using immunohistochemistry. The correlation between GPER expression and clinicopathological characteristics was analyzed. The expression of GPER in cervical cancer tissues was significantly higher than that in paracancerous tissues, and it was detected in the membrane and cytoplasm of SiHa and HeLa cells. The proliferation, migration, and invasion abilities of SiHa and HeLa cells were reduced after G15 treatment. The G15-treated groups exhibited higher expression of E-cadherin and Bax and lower expression of N-cadherin, vimentin, Bcl-2, GPER, p-PI3K, p-AKT, and PD-L1 than the control group. The expression of E-cadherin was lower and that of vimentin was higher in cancer tissues than in paracancerous tissues; PD-L1 was highly expressed in tumor and stromal cells in cancer tissues but not in paracancerous tissues. G15 functions by regulating the GPER/PI3K/AKT/PD-L1 signaling pathway and may serve as a new immunotherapy for treating patients with cervical cancer.


Assuntos
Proliferação de Células , Receptores de Estrogênio , Receptores Acoplados a Proteínas G , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Estrogênio/metabolismo , Proliferação de Células/efeitos dos fármacos , Células HeLa , Movimento Celular/efeitos dos fármacos , Pessoa de Meia-Idade , Antígeno B7-H1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Vimentina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Caderinas/metabolismo , Ciclopentanos , Quinolinas
11.
Mol Breed ; 44(10): 72, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39399692

RESUMO

Deterioration of rice (Oryza sativa L.) affects grain quality and seed viability during storage. Lipoxygenase (LOX), a key enzyme in lipid metabolism, directly affects the rate of ageing. Here, we found that knock-out of lipoxygenase gene OsLOX1 by CRISPR/Cas9 delayed loss of seed viability and quality. Transcriptome analysis showed that during storage, OsLOX1 affected transcription of multiple genes, including genes related to lipid metabolism and antioxidant pathways such as phosphatase and acetaldehyde dehydrogenase, which may regulate the seed storability. The genes significantly down- and up-regulated only in Ningjing 4 after NA for 13 months and 3 days of AA suggesting that OsLOX1 likely promoted seed viability in rice by balancing ageing and storage related genes, and regulated the seed storability through the amino acid synthesis and metabolic pathways. Moreover, knock-out of OsLOX1 without CRISPR/Cas9 not only improved the seed viability, but also had little impact on agronomic traits. More importantly, the OsLOX1 knock-out lines were approved in 2019 (Agricultural Foundation of China Report No. 770). Collectively, our study showed that knock-out of OsLOX1 is beneficial for prolongation of seed viability and can be directly applied to agricultural production. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01506-4.

12.
Transfus Med ; 34(1): 39-45, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37950522

RESUMO

OBJECTIVES: This study aimed to investigate the molecular mechanism of the Jk(a-b-) phenotype in a Chinese transfusion patient. BACKGROUND: Many different mutation types relating to Jk(a-b-) phenotype have been reported. However, the splice-site mutation is relatively rare and the related functional verification is lacking. MATERIALS AND METHODS: In this study, the blood sample was collected from a transfusion patient with the Jk(a-b-) phenotype. Serotyping was performed using routine serological methods. The exons sequences and coding regions of the JK gene were amplified using polymerase chain reaction and directly sequenced. To perform a minigene splicing assay, the intronic mutation sequences were cloned into a pSPL3 splice reporting vector. The splicing reporter minigene assay was performed in HEK 293T cells. RESULTS: The Jk(a-b-) phenotype of the blood sample was identified through serological testing. Sequencing results revealed that the sample had a novel homozygous splice-site mutation JK*02N (NM_015865.7: c.663+3A>C). Further analysis, including cDNA sequencing and minigene splicing assay, confirmed that the novel splice-site mutation resulted in exon skipping. Interestingly, different numbers of exons being skipped were obtained by the two methods. CONCLUSION: This study revealed a novel homozygous splicing-site mutation associated with the Jk(a-b-) phenotype in Chinese population. Our results emphasise the importance of the in vitro functional method minigene splicing assay, while also acknowledging its potential limitations when compared to cDNA sequencing.


Assuntos
Splicing de RNA , Humanos , DNA Complementar , Mutação , Éxons/genética , Fenótipo
13.
Sensors (Basel) ; 24(17)2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39275770

RESUMO

Additive manufacturing (AM) excels in engineering intricate shapes, pioneering functional components, and lightweight structures. Nevertheless, components fabricated through AM often manifest elevated residual stresses and a myriad of thermally induced micro-instabilities, including cracking, incomplete fusion, crazing, porosity, spheroidization, and inclusions. In response, this study proposed a sophisticated multi-sensing inspection system specifically tailored for the inspection of thermally induced micro-instabilities at the micro-nano scale. Simulation results substantiate that the modulation transfer function (MTF) values for each field of view in both visible and infrared optical channels surpass the benchmark of 0.3, ensuring imaging fidelity conducive to meticulous examination. Furthermore, the innovative system can discern and accurately capture data pertaining to thermally induced micro-instabilities across visible and infrared spectra, seamlessly integrating this information into a backend image processing system within operational parameters of a 380-450 mm distance and a 20-70 °C temperature range. Notably, the system's design is harmoniously aligned with the requisites of processing and assembly, heralding a significant advancement in bolstering the inspection effect of thermally induced micro-instabilities for the AM component.

14.
Sensors (Basel) ; 24(11)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38894056

RESUMO

Energy efficiency and data reliability are important indicators to measure network performance in wireless sensor networks. In existing research schemes of routing protocols, the impact of node coverage on the network is often ignored, and the possibility that multiple sensor nodes may sense the same spatial point is not taken into account, which results in a waste of network resources, especially in large-scale networks. Apart from that, the blindness of geographic routing in data transmission has been troubling researchers, which means that the nodes are unable to determine the validity of data transmission. In order to solve the above problems, this paper innovatively combines the routing protocol with the coverage control technique and proposes the node collaborative scheduling algorithm, which fully considers the correlation characteristics between sensor nodes to reduce the number of active working nodes and the number of packets generated, to further reduce energy consumption and network delay and improve packet delivery rate. In order to solve the problem of unreliability of geographic routing, a highly reliable link detection and repair scheme is proposed to check the communication link status and repair the invalid link, which can greatly improve the packet delivery rate and throughput of the network, and has good robustness. A large number of experiments demonstrate the effectiveness and superiority of our proposed scheme and algorithm.

15.
Nano Lett ; 23(8): 3137-3143, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37036942

RESUMO

Twisted van der Waals multilayers are widely regarded as a rich platform to access novel electronic phases thanks to the multiple degrees of freedom available for controlling their electronic and chemical properties. Here, we propose that the stacking domains that form naturally due to the relative twist between successive layers act as an additional "knob" for controlling the behavior of these systems and report the emergence and engineering of stacking domain-dependent surface chemistry in twisted few-layer graphene. Using mid-infrared near-field optical microscopy and atomic force microscopy, we observe a selective adhesion of metallic nanoparticles and liquid water at the domains with rhombohedral stacking configurations of minimally twisted double bi- and trilayer graphene. Furthermore, we demonstrate that the manipulation of nanoparticles located at certain stacking domains can locally reconfigure the moiré superlattice in their vicinity at the micrometer scale. Our findings establish a new approach to controlling moiré-assisted chemistry and nanoengineering.

16.
Transfus Med ; 33(4): 297-305, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36971189

RESUMO

OBJECTIVE: Investigation of a Jr(a-) family samples, identification of the mutant and assessment of the differences of Jr antigen density of the Jr(a-) family members, random adult and newborn individuals' RBCs. BACKGROUND: The anti-Jra antibody is generated when a Jr(a-) individual pregnant or transfused with Jr(a+) blood unit, which can lead to mild-to-moderate hemolytic disease of the foetus and newborn (HDFN) or hemolytic transfusion reaction (HTR). Several mutations had been identified. The anti-Jra caused HDFN is not rare in East Asia, but due to the lack of antibody and molecular background, it is likely to lead missed detection. METHODS AND MATERIALS: One G4P1 woman had been detected as IAT positive during prenatal examination. Suspected as anti-Jra after the laboratory serological testing, the maternal sample was further assessed by molecular analysis. The antigen density was detected by flow cytometry after reacting with anti-Jra serum in family members and the normal individuals. RESULTS: One novel frameshift mutation c.717delC and one previously identified mutation c.706C > T in ABCG2 was identified on proband. The infant haemoglobin(Hb) and bilirubin increased significantly after exchange transfusion and the severe HDFN was relieved. Flow cytometry results showed that the Jra antigens on adult RBCs were significantly less than those on the infant. CONCLUSION: The c.717delC mutation can lead to the shortening of protein ABCG2 in the site of p.Leu307Stop, result in the loss of Jra antigen. The difference in antigen density between adult and infant RBCs may be a possible reason that leads to severe HDFN but not transfusion reaction. Breastfeeding may lead to slower recovery from HDFN.


Assuntos
Antígenos de Grupos Sanguíneos , Eritroblastose Fetal , Adulto , Feminino , Gravidez , Recém-Nascido , Humanos , Mães , População do Leste Asiático , Antígenos de Grupos Sanguíneos/genética , Hemólise , Mutação , Hemoglobinas , Isoanticorpos
17.
Biochem Genet ; 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37906301

RESUMO

Dysomma anguillare is a demersal eel widespread distributing in tropical waters of the Indo-West Pacific and Atlantic. As an important component of the coastal fishery and marine ecosystem, the lack of genomic information for this species severely restricts the progress of relevant researches. In this study, the abecedarian genome-wide characteristics and phylogenetic relationships analyses were carried out based on next-generation sequencing (NGS) platform. The revised genome size was approximately 1 310 Mb, with the largest scaffold length reaching 23 878 bp through K-mer (K = 17) method. The heterozygosity, repetitive rate and average GC content were about 0.94%, 51.93% and 42.23%, respectively. A total of 1 160 104 microsatellite motifs were identified from the de novo assembled genome of D. anguillare, in which dinucleotide repeats accounted for the largest proportion (592 234, 51.05%), the highest occurrence frequency (14.58%) as well as the largest relative abundance (379.27/Mb). The high-polymorphic and moderate-polymorphic loci composed around 73% of the total single sequence repeats (SSRs), showing a latent capacity for subsequent population genetic structure and genetic diversity appraisal researches. Another byproduct of whole-genome sequencing, the double-stranded and circular mitogenome (16 690 bp) was assembled to investigate the evolutionary relationships of D. anguillare. The phylogenic tree constructed with maximum likelihood (ML) method showed that D. anguillare was closely related to Synaphobranchidae species, and the molecular systematic results further supported classical taxonomy status of D. anguillare.

18.
Vox Sang ; 117(7): 949-957, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35510963

RESUMO

BACKGROUND AND OBJECTIVES: In cases of serologically weak D phenotypes, RHD genotyping may identify discrepant serotyping results and protect the patient against allogeneic immunization. This study aimed to conduct a comprehensive analysis of weak D alleles in China. MATERIALS AND METHODS: We collected samples carrying weak D antigen during a 10-year period from 2005 to 2014. The intensity and epitopes of D were analysed serologically. Genomic DNA was extracted and used for RHD sequencing and heterozygote analysis. In particular, an in vitro expression method for functional verification of the rare and novel in-frame deletion mutation was developed and then combined with homologous modelling results for analysis. RESULTS: We studied a total of 283 weak D samples from volunteer blood donors and identified 45 RHD alleles among them, 11 of which were reported for the first time. Ten (3.5%) samples surprisingly carried DEL allelic variants and as many as 40 (14.1%) carried the wild-type RHD genotype. Combination of the results of functional experiments and in silico analysis suggested that the rare in-frame deletion mutation may reduce the expression of D antigen by affecting the RhD protein structure. CONCLUSIONS: This study provides an enhanced overview of the distribution characteristics of RHD alleles in Chinese subjects with serologically weak D. An in vitro method to predict the biological significance of variant RHD alleles was also provided. We found inconsistent genotyping and phenotypic results in some samples, indicating the existence of additional regulatory mechanisms.


Assuntos
Antígenos de Grupos Sanguíneos , Sistema do Grupo Sanguíneo Rh-Hr , Alelos , Genótipo , Humanos , Fenótipo , Sistema do Grupo Sanguíneo Rh-Hr/genética
19.
Int J Colorectal Dis ; 37(6): 1449-1464, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35482069

RESUMO

PURPOSE: DNA mismatch repair (MMR) protein deficiency has attached more attention for its potential to be a biomarker of immunotherapy for colorectal cancer (CRC) patients. However, clinical models involving the expression status of MMR protein are rare. Herein, we sought to develop two clinical models (a diagnostic model for the prediction of MMR status and a prognostic model for the prediction of disease-free survival) for CRC patients. METHODS: A total of 582 CRC patients were finally included. There were 53 patients with deficient expression of MMR protein. The differences between the deficient MMR (dMMR) group and the proficient MMR (pMMR) group were analyzed. RESULTS: Compared to pMMR patients, those with dMMR status were younger and had better pathological features (depth of invasion, lymph node metastasis, distant metastasis, pathological stage, perineuronal invasion, and PLT level) and disease-free survival (DFS). The tumor location of the left colon, adenocarcinoma, and abnormal PLT level were identified as the independent predictors for pMMR. Based on these data, we developed the diagnostic model using Logistic regression analysis. It showed a satisfactory accuracy (AUC = 82.3% in the derivate set; AUC = 73.6% in the validation set). Furthermore, pMMR, poorer differentiation, perineuronal invasion, distant metastasis, lower hemoglobin level, and abnormal CEA level were established as the independent prognostic factors of poorer DFS. Based on them, a prognostic model with valuable performance (1-year AUC = 75.5%/3-year AUC = 76.9% in the derivate set; 1-year AUC = 72.3%/3-year AUC = 73.8% in the validation set) was developed. CONCLUSIONS: Our diagnostic and prognostic models could identify CRC patients at risk for pMMR protein expression and disease recurrence. It may contribute to improving the diagnosis and treatment of CRC patients at an individual level.


Assuntos
Neoplasias Colorretais , Deficiência de Proteína , Neoplasias Encefálicas , Neoplasias Colorretais/patologia , Reparo de Erro de Pareamento de DNA/genética , Intervalo Livre de Doença , Humanos , Recidiva Local de Neoplasia , Síndromes Neoplásicas Hereditárias , Prognóstico
20.
Plant Cell Rep ; 41(10): 2107-2110, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35976402

RESUMO

KEY MESSAGE: Knock out OsABA8ox helps improve pre-harvest spouting resistance and do not affect rice yield. Pre-harvest sprouting(PHS) is a phenomenon that the seeds of crops germinate preharvest, which reduces the yield and quality of rice. Abscisic acid(ABA) is one of the phytohormones that promotes seed dormancy. ABA8' hydroxylase is the main enzyme that can catabolism ABA in plant. There are three genes that encode ABA8' hydroxylase in rice, named OsABA8ox1, OsABA8ox2 and OsABA8ox3. In this study, we use CRISPR/Cas9 gene editing technology to target these three genes in Ningjing6 and find that the knockout transgenic lines are all significantly strengthen in seed dormancy and have no effect on the yield. By a series of quantitative experiments, we consider that after knock out OsABA8ox, the high endogenous ABA level will influence the ABA signal which suppress the substantial and energy metabolism in the seeds, and finally led to higher dormancy.


Assuntos
Oryza , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Sistemas CRISPR-Cas/genética , Regulação da Expressão Gênica de Plantas , Germinação/genética , Oxigenases de Função Mista/genética , Oryza/genética , Oryza/metabolismo , Dormência de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/metabolismo
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