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1.
Nature ; 609(7928): 741-746, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35772670

RESUMO

The January 2022 Hunga Tonga-Hunga Ha'apai eruption was one of the most explosive volcanic events of the modern era1,2, producing a vertical plume that peaked more than 50 km above the Earth3. The initial explosion and subsequent plume triggered atmospheric waves that propagated around the world multiple times4. A global-scale wave response of this magnitude from a single source has not previously been observed. Here we show the details of this response, using a comprehensive set of satellite and ground-based observations to quantify it from surface to ionosphere. A broad spectrum of waves was triggered by the initial explosion, including Lamb waves5,6 propagating at phase speeds of 318.2 ± 6 m s-1 at surface level and between 308 ± 5 to 319 ± 4 m s-1 in the stratosphere, and gravity waves7 propagating at 238 ± 3 to 269 ± 3 m s-1 in the stratosphere. Gravity waves at sub-ionospheric heights have not previously been observed propagating at this speed or over the whole Earth from a single source8,9. Latent heat release from the plume remained the most significant individual gravity wave source worldwide for more than 12 h, producing circular wavefronts visible across the Pacific basin in satellite observations. A single source dominating such a large region is also unique in the observational record. The Hunga Tonga eruption represents a key natural experiment in how the atmosphere responds to a sudden point-source-driven state change, which will be of use for improving weather and climate models.

2.
Nature ; 587(7834): 420-425, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33177709

RESUMO

Genome introgressions drive evolution across the animal1, plant2 and fungal3 kingdoms. Introgressions initiate from archaic admixtures followed by repeated backcrossing to one parental species. However, how introgressions arise in reproductively isolated species, such as yeast4, has remained unclear. Here we identify a clonal descendant of the ancestral yeast hybrid that founded the extant Saccharomyces cerevisiae Alpechin lineage5, which carries abundant Saccharomyces paradoxus introgressions. We show that this clonal descendant, hereafter defined as a 'living ancestor', retained the ancestral genome structure of the first-generation hybrid with contiguous S. cerevisiae and S. paradoxus subgenomes. The ancestral first-generation hybrid underwent catastrophic genomic instability through more than a hundred mitotic recombination events, mainly manifesting as homozygous genome blocks generated by loss of heterozygosity. These homozygous sequence blocks rescue hybrid fertility by restoring meiotic recombination and are the direct origins of the introgressions present in the Alpechin lineage. We suggest a plausible route for introgression evolution through the reconstruction of extinct stages and propose that genome instability allows hybrids to overcome reproductive isolation and enables introgressions to emerge.


Assuntos
Evolução Molecular , Introgressão Genética/genética , Genoma Fúngico/genética , Genômica , Filogenia , Saccharomyces cerevisiae/genética , Saccharomyces/genética , Cruzamentos Genéticos , Fertilidade/genética , Aptidão Genética/genética , Instabilidade Genômica/genética , Recombinação Homóloga/genética , Perda de Heterozigosidade/genética , Meiose/genética , Mitose/genética , Reprodução Assexuada/genética , Saccharomyces/classificação , Saccharomyces/citologia , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/citologia
3.
PLoS Genet ; 19(11): e1011012, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37931001

RESUMO

The mutational processes dictating the accumulation of mutations in genomes are shaped by genetic background, environment and their interactions. Accurate quantification of mutation rates and spectra under drugs has important implications in disease treatment. Here, we used whole-genome sequencing and time-resolved growth phenotyping of yeast mutation accumulation lines to give a detailed view of the mutagenic effects of rapamycin and hydroxyurea on the genome and cell growth. Mutation rates depended on the genetic backgrounds but were only marginally affected by rapamycin. As a remarkable exception, rapamycin treatment was associated with frequent chromosome XII amplifications, which compensated for rapamycin induced rDNA repeat contraction on this chromosome and served to maintain rDNA content homeostasis and fitness. In hydroxyurea, a wide range of mutation rates were elevated regardless of the genetic backgrounds, with a particularly high occurrence of aneuploidy that associated with dramatic fitness loss. Hydroxyurea also induced a high T-to-G and low C-to-A transversion rate that reversed the common G/C-to-A/T bias in yeast and gave rise to a broad range of structural variants, including mtDNA deletions. The hydroxyurea mutation footprint was consistent with the activation of error-prone DNA polymerase activities and non-homologues end joining repair pathways. Taken together, our study provides an in-depth view of mutation rates and signatures in rapamycin and hydroxyurea and their impact on cell fitness, which brings insights for assessing their chronic effects on genome integrity.


Assuntos
Hidroxiureia , Saccharomyces cerevisiae , Humanos , Hidroxiureia/farmacologia , Saccharomyces cerevisiae/genética , Sirolimo/farmacologia , Mutação , Instabilidade Genômica/genética , DNA Ribossômico/genética
4.
Nucleic Acids Res ; 51(10): 5228-5241, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37070178

RESUMO

Conversely to canonical splicing, back-splicing connects the upstream 3' splice site (SS) with a downstream 5'SS and generates exonic circular RNAs (circRNAs) that are widely identified and have regulatory functions in eukaryotic gene expression. However, sex-specific back-splicing in Drosophila has not been investigated and its regulation remains unclear. Here, we performed multiple RNA analyses of a variety sex-specific Drosophila samples and identified over ten thousand circular RNAs, in which hundreds are sex-differentially and -specifically back-spliced. Intriguingly, we found that expression of SXL, an RNA-binding protein encoded by Sex-lethal (Sxl), the master Drosophila sex-determination gene that is only spliced into functional proteins in females, promoted back-splicing of many female-differential circRNAs in the male S2 cells, whereas expression of a SXL mutant (SXLRRM) did not promote those events. Using a monoclonal antibody, we further obtained the transcriptome-wide RNA-binding sites of SXL through PAR-CLIP. After splicing assay of mini-genes with mutations in the SXL-binding sites, we revealed that SXL-binding on flanking exons and introns of pre-mRNAs facilitates back-splicing, whereas SXL-binding on the circRNA exons inhibits back-splicing. This study provides strong evidence that SXL has a regulatory role in back-splicing to generate sex-specific and -differential circRNAs, as well as in the initiation of sex-determination cascade through canonical forward-splicing.


Assuntos
Proteínas de Drosophila , RNA Circular , Proteínas de Ligação a RNA , Animais , Feminino , Masculino , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , RNA/genética , RNA/metabolismo , Splicing de RNA/genética , RNA Circular/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
5.
PLoS Genet ; 18(5): e1010047, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35533184

RESUMO

Meiotic recombination is an essential biological process that ensures faithful chromosome segregation and promotes parental allele shuffling. Tetrad analysis is a powerful approach to quantify the genetic makeups and recombination landscapes of meiotic products. Here we present RecombineX (https://github.com/yjx1217/RecombineX), a generalized computational framework that automates the full workflow of marker identification, gamete genotyping, and tetrad-based recombination profiling based on any organism or genetic background with batch processing capability. Aside from conventional reference-based analysis, RecombineX can also perform analysis based on parental genome assemblies, which facilitates analyzing meiotic recombination landscapes in their native genomic contexts. Additional features such as copy number variation profiling and missing genotype inference further enhance downstream analysis. RecombineX also includes a dedicate module for simulating the genomes and reads of recombinant tetrads, which enables fine-tuned simulation-based hypothesis testing. This simulation module revealed the power and accuracy of RecombineX even when analyzing tetrads with very low sequencing depths (e.g., 1-2X). Tetrad sequencing data from the budding yeast Saccharomyces cerevisiae and green alga Chlamydomonas reinhardtii were further used to demonstrate the accuracy and robustness of RecombineX for organisms with both small and large genomes, manifesting RecombineX as an all-around one stop solution for future tetrad analysis. Interestingly, our re-analysis of the budding yeast tetrad sequencing data with RecombineX and Oxford Nanopore sequencing revealed two unusual structural rearrangement events that were not noticed before, which exemplify the occasional genome instability triggered by meiosis.


Assuntos
Variações do Número de Cópias de DNA , Meiose , Genótipo , Células Germinativas , Recombinação Homóloga , Meiose/genética , Saccharomyces cerevisiae/genética
6.
J Neurosci ; 43(47): 8018-8031, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37752000

RESUMO

The identifiable target effect refers to the preference for helping identified victims and punishing identifiable perpetrators compared with equivalent but unidentifiable counterparts. The identifiable target effect is often attributed to the heightened moral emotions evoked by identified targets. However, the specific neurocognitive processes that mediate and/or modulate this effect remain largely unknown. Here, we combined a third-party punishment game with brain imaging and computational modeling to unravel the neurocomputational underpinnings of the identifiable transgressor effect. Human participants (males and females) acted as bystanders and punished identified or anonymous wrongdoers. Participants were more punitive toward identified wrongdoers than anonymous wrongdoers because they took a vicarious perspective of victims and adopted lower reference points of inequity (i.e., more stringent norms) in the identified context than in the unidentified context. Accordingly, there were larger activity of the ventral anterior insula, more distinct multivariate neural patterns in the dorsal anterior insula and dorsal anterior cingulate cortex, and lower strength between ventral anterior insula and dorsolateral PFC and between dorsal anterior insula and ventral striatum connectivity in response to identified transgressors than anonymous transgressors. These findings implicate the interplay of expectancy violations, emotions, and self-interest in the identifiability effect. Last, individual differences in the identifiability effect were associated with empathic concern/social dominance orientation, activity in the precuneus/cuneus and temporo-parietal junction, and intrinsic functional connectivity of the dorsolateral PFC. Together, our work is the first to uncover the neurocomputational processes mediating identifiable transgressor effect and to characterize psychophysiological profiles modulating the effect.SIGNIFICANCE STATEMENT The identifiable target effect, more help to identified victims or stronger punishment to identifiable perpetrators, is common in daily life. We examined the neurocomputational mechanisms mediating/modulating the identifiability effect on third-party punishment by bridging literature from economics and cognitive neuroscience. Our findings reveal that identifiable transgressor effect is mediated by lower reference points of inequity (i.e., more stringent norms), which might be associated with a stronger involvement of the emotion processes and a weaker engagement of the analytic/deliberate processes. Furthermore, personality traits, altered brain activity, and intrinsic functional connectivity contribute to the individual variance in the identifiability effect. Overall, our study advances the understanding of the identifiability effect by shedding light on its component processes and modulating factors.


Assuntos
Encéfalo , Punição , Masculino , Feminino , Humanos , Punição/psicologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Emoções/fisiologia , Mapeamento Encefálico , Empatia , Imageamento por Ressonância Magnética
7.
Infect Immun ; 92(3): e0003824, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38391206

RESUMO

Histophilus somni is one of the predominant bacterial pathogens responsible for bovine respiratory and systemic diseases in cattle. Despite the identification of numerous H. somni virulence factors, little is known about the regulation of such factors. The post-transcriptional regulatory protein Hfq may play a crucial role in regulation of components that affect bacterial virulence. The contribution of Hfq to H. somni phenotype and virulence was investigated following creation of an hfq deletion mutant of H. somni strain 2336 (designated H. somni 2336Δhfq). A comparative analysis of the mutant to the wild-type strain was carried out by examining protein and carbohydrate phenotype, RNA sequence, intracellular survival in bovine monocytes, serum susceptibility, and virulence studies in mouse and calf models. H. somni 2336Δhfq exhibited a truncated lipooligosaccharide (LOS) structure, with loss of sialylation. The mutant demonstrated increased susceptibility to intracellular and serum-mediated killing compared to the wild-type strain. Transcriptomic analysis displayed significant differential expression of 832 upregulated genes and 809 downregulated genes in H. somni 2336Δhfq compared to H. somni strain 2336, including significant downregulation of lsgB and licA, which contribute to LOS oligosaccharide synthesis and sialylation. A substantial number of differentially expressed genes were associated with polysaccharide synthesis and other proteins that could influence virulence. The H. somni 2336Δhfq mutant strain was attenuated in a mouse septicemia model and somewhat attenuated in a calf intrabronchial challenge model. H. somni was recovered less frequently from nasopharyngeal swabs, endotracheal aspirates, and lung tissues of calves challenged with H. somni 2336Δhfq compared to the wild-type strain, and the percentage of abnormal lung tissue in calves challenged with H. somni 2336Δhfq was lower than in calves challenged with the wild-type strain. In conclusion, our results support that Hfq accounts for the regulation of H. somni virulence factors.


Assuntos
Haemophilus somnus , Pasteurellaceae , Animais , Bovinos , Camundongos , Virulência/genética , Haemophilus somnus/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Proteínas/metabolismo , Monócitos , Pasteurellaceae/genética
8.
Neuroimage ; 298: 120773, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39122058

RESUMO

Non-invasive neuroimaging has revealed specific network-based resting-state dynamics in the human brain, yet the underlying neurophysiological mechanism remains unclear. We employed intracranial electroencephalography to characterize local field potentials within the default mode network (DMN), frontoparietal network (FPN), and salience network (SN) in 42 participants. We identified stronger within-network phase coherence at low frequencies (θ and α band) within the DMN, and at high frequencies (γ band) within the FPN. Hidden Markov modeling indicated that the DMN exhibited preferential low frequency phase coupling. Phase-amplitude coupling (PAC) analysis revealed that the low-frequency phase in the DMN modulated the high-frequency amplitude envelopes of the FPN, suggesting frequency-dependent characterizations of intrinsic brain networks at rest. These findings provide intracranial electrophysiological evidence in support of the network model for intrinsic organization of human brain and shed light on the way brain networks communicate at rest.


Assuntos
Encéfalo , Rede Nervosa , Humanos , Masculino , Feminino , Adulto , Rede Nervosa/fisiologia , Rede Nervosa/diagnóstico por imagem , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Rede de Modo Padrão/fisiologia , Rede de Modo Padrão/diagnóstico por imagem , Adulto Jovem , Eletrocorticografia , Eletroencefalografia/métodos
9.
Yeast ; 41(1-2): 19-34, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38041528

RESUMO

Genetic targeting (e.g., gene knockout and tagging) based on polymerase chain reaction (PCR) is a simple yet powerful approach for studying gene functions. Although originally developed in classic budding and fission yeast models, the same principle applies to other eukaryotic systems with efficient homologous recombination. One-step PCR-based genetic targeting is conventionally used but the sizes of the homologous arms that it generates for recombination-mediated genetic targeting are usually limited. Alternatively, gene targeting can also be performed via fusion PCR, which can create homologous arms that are orders of magnitude larger, therefore substantially increasing the efficiency of recombination-mediated genetic targeting. Here, we present GetPrimers (https://www.evomicslab.org/app/getprimers/), a generalized computational framework and web tool to assist automatic targeting and verification primer design for both one-step PCR-based and fusion PCR-based genetic targeting experiments. Moreover, GetPrimers by design runs for any given genetic background of any species with full genome scalability. Therefore, GetPrimers is capable of empowering high-throughput functional genomic assays at multipopulation and multispecies levels. Comprehensive experimental validations have been performed for targeting and verification primers designed by GetPrimers across multiple organism systems and experimental setups. We anticipate GetPrimers to become a highly useful and popular tool to facilitate easy and standardized gene modification across multiple systems.


Assuntos
Marcação de Genes , Schizosaccharomyces , Recombinação Homóloga , Técnicas de Inativação de Genes , Sequência de Bases , Schizosaccharomyces/genética , Reação em Cadeia da Polimerase
10.
J Transl Med ; 22(1): 742, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107788

RESUMO

BACKGROUND: LARC patients commonly receive adjuvant therapy, however, hidden micrometastases still limit the improvement of OS. This study aims to investigate the impact of VASN in rectal cancer with pulmonary metastasis and understand the underlying molecular mechanisms to guide adjuvant chemotherapy selection. METHODS: Sequencing data from rectal cancer patients with pulmonary metastasis from Sun Yat-sen University Cancer Center (SYSUCC) and publicly available data were meticulously analyzed. The functional role of VASN in pulmonary metastasis was validated in vivo and in vitro. Coimmunoprecipitation (co-IP), immunofluorescence, and rescue experiments were conducted to unravel potential molecular mechanisms of VASN. Moreover, VASN expression levels in tumor samples were examined and analyzed for their correlations with pulmonary metastasis status, tumor stage, adjuvant chemotherapy benefit, and survival outcome. RESULTS: Our study revealed a significant association between high VASN expression and pulmonary metastasis in LARC patients. Experiments in vitro and in vivo demonstrated that VASN could promote the cell proliferation, metastasis, and drug resistance of colorectal cancer. Mechanistically, VASN interacts with the NOTCH1 protein, leading to concurrent activation of the NOTCH and MAPK pathways. Clinically, pulmonary metastasis and advanced tumor stage were observed in 90% of VASN-positive patients and 53.5% of VASN-high patients, respectively, and VASN-high patients had a lower five-year survival rate than VASN-low patients (26.7% vs. 83.7%). Moreover, the Cox analysis and OS analysis indicated that VASN was an independent prognostic factor for OS (HR = 7.4, P value < 0.001) and a predictor of adjuvant therapy efficacy in rectal cancer. CONCLUSIONS: Our study highlights the role of VASN in decreasing drug sensitivity and activating the NOTCH and MAPK pathways, which leads to tumorigenesis and pulmonary metastasis. Both experimental and clinical data support that rectal cancer patients with VASN overexpression detected in biopsies have a higher risk of pulmonary metastasis and adjuvant chemotherapy resistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares , Neoplasias Retais , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Feminino , Masculino , Neoplasias Retais/patologia , Neoplasias Retais/metabolismo , Neoplasias Retais/genética , Neoplasias Retais/tratamento farmacológico , Quimioterapia Adjuvante , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Pessoa de Meia-Idade , Animais , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Proliferação de Células/efeitos dos fármacos , Receptor Notch1/metabolismo , Receptor Notch1/genética , Proteínas dos Microfilamentos/metabolismo , Proteínas dos Microfilamentos/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos
11.
Opt Lett ; 49(19): 5563-5566, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353007

RESUMO

Metalenses, boasting outstanding focusing efficiency and high-resolution imaging capabilities, have generated widespread usage in fields such as integrated optics, achromatic imaging, and optical holography. In this study, we have developed a broadband achromatic metalens within the detection range from 3 to 5 µm, and it has a numerical aperture (NA) of 0.71 with a remarkable maximum focusing efficiency of 63.8% at the focal plane within the specified bandwidth. We have further delved into the dispersion control mechanism that combines the geometric and transmission phases and optimized the constructed phase response simulation database using the particle swarm optimization (PSO) algorithm, ensuring a precise phase matching between the actual wavefront and the ideal focusing wavefront. This metalens with its ability to expand the array size has the potential to create a compact infrared imager, which holds significant importance in achieving efficient detection and integration within infrared detectors.

12.
Nature ; 556(7701): 339-344, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29643504

RESUMO

Large-scale population genomic surveys are essential to explore the phenotypic diversity of natural populations. Here we report the whole-genome sequencing and phenotyping of 1,011 Saccharomyces cerevisiae isolates, which together provide an accurate evolutionary picture of the genomic variants that shape the species-wide phenotypic landscape of this yeast. Genomic analyses support a single 'out-of-China' origin for this species, followed by several independent domestication events. Although domesticated isolates exhibit high variation in ploidy, aneuploidy and genome content, genome evolution in wild isolates is mainly driven by the accumulation of single nucleotide polymorphisms. A common feature is the extensive loss of heterozygosity, which represents an essential source of inter-individual variation in this mainly asexual species. Most of the single nucleotide polymorphisms, including experimentally identified functional polymorphisms, are present at very low frequencies. The largest numbers of variants identified by genome-wide association are copy-number changes, which have a greater phenotypic effect than do single nucleotide polymorphisms. This resource will guide future population genomics and genotype-phenotype studies in this classic model system.


Assuntos
Evolução Molecular , Variação Genética , Genoma Fúngico/genética , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/genética , Alelos , Aneuploidia , China , Variações do Número de Cópias de DNA , Estudos de Associação Genética , Estudo de Associação Genômica Ampla , Genômica , Perda de Heterozigosidade , Fenótipo , Filogenia , Filogeografia , Ploidias , Polimorfismo de Nucleotídeo Único , Saccharomyces cerevisiae/isolamento & purificação , Análise de Sequência de DNA
13.
Cereb Cortex ; 33(5): 2061-2074, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36857720

RESUMO

Cognitive processing relies on the functional coupling between the cerebrum and cerebellum. However, it remains unclear how the 2 collaborate in amnestic mild cognitive impairment (aMCI) patients. With functional magnetic resonance imaging techniques, we compared cerebrocerebellar functional connectivity during the resting state (rsFC) between the aMCI and healthy control (HC) groups. Additionally, we distinguished coupling between functionally corresponding and noncorresponding areas across the cerebrum and cerebellum. The results demonstrated decreased rsFC between both functionally corresponding and noncorresponding areas, suggesting distributed deficits of cerebrocerebellar connections in aMCI patients. Increased rsFC was also observed, which were between functionally noncorresponding areas. Moreover, the increased rsFC was positively correlated with attentional scores in the aMCI group, and this effect was absent in the HC group, supporting that there exists a compensatory mechanism in patients. The current study contributes to illustrating how the cerebellum adjusts its coupling with the cerebrum in individuals with cognitive impairment.


Assuntos
Cérebro , Disfunção Cognitiva , Humanos , Telencéfalo , Cerebelo , Nível de Saúde
14.
Environ Res ; 252(Pt 1): 118881, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582430

RESUMO

Nitrate reduction in bio-electrochemical systems (BESs) has attracted wide attention due to its low sludge yields and cost-efficiency advantages. However, the high resistance of traditional electrodes is considered to limit the denitrification performance of BESs. Herein, a new graphene/polypyrrole (rGO/PPy) modified electrode is fabricated via one-step electrodeposition and used as cathode in BES for improving nitrate removal from wastewater. The formation and morphological results support the successful formation of rGO/PPy nanohybrids and confirm the part covalent bonding of Py into GO honeycomb lattices to form a three-dimensional cross-linked spatial structure. The electrochemical tests indicate that the rGO/PPy electrode outperforms the unmodified electrode due to the 3.9-fold increase in electrochemical active surface area and 6.9-fold decrease in the charge transfer resistance (Rct). Batch denitrification activity tests demonstrate that the BES equipped with modified rGO/PPy biocathode could not only achieve the full denitrification efficiency of 100% with energy recovery (15.9 × 10-2 ± 0.14 A/m2), but also favor microbial attach and growth with improved biocompatible surface. This work provides a feasible electrochemical route to fabricate and design a high-performance bioelectrode to enhance denitrification in BESs.


Assuntos
Desnitrificação , Eletrodos , Grafite , Polímeros , Pirróis , Grafite/química , Polímeros/química , Pirróis/química , Técnicas Eletroquímicas/métodos , Fontes de Energia Bioelétrica , Nitratos/química , Carbono/química , Fibra de Carbono/química
15.
Zhonghua Nan Ke Xue ; 30(3): 199-208, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-39177385

RESUMO

OBJECTIVE: To explore the potential impact of lipid metabolism-related single nucleotide polymorphisms (SNP) on semen quality in men. METHODS: We selected 284 semen samples from Xingtai Infertility Hospital and Hebei Human Sperm Bank collected between February and October 2023, 33 from oligozoospermia (OS), 97 from asthenozoospermia (AS) and 54 from oligoasthenozoospermia (OAS) patients and the other 100 from normal men. We performed computer-assisted semen analysis (CASA) of the samples, extracted blood DNA and, using the MassARRAY System, genotyped the target genes, determined the genotypes of 13 SNPs and compared their distribution, their correlation with BMI and semen quality in different groups. RESULTS: The mutant homozygous (TT) genotype of the FADS2 rs2727270 gene seemed to be a risk factor for AS (OR = 4.420, P= 0.047), while the APOA2 rs5082-A allele and MC4R rs17782313 heterozygous (TC) genotype important protective factors for OS (OR = 0.422 and 0.389; P= 0.045 and 0.043, respectively). A significantly higher sperm concentration was found associated with the MC4R rs17782313 heterozygous (TC) genotype than with the homozygous (CC) genotype. Stratification analysis showed that the protective effect of the TC genotype was decreased with increased BMI and remained with the interaction of the rs5082 and rs17782313 genotypes. CONCLUSION: FADS2 rs2727270, APOA2 rs5082 and MC4R rs17782313 were significantly correlated with the risk of abnormal semen parameters.


Assuntos
Genótipo , Metabolismo dos Lipídeos , Polimorfismo de Nucleotídeo Único , Análise do Sêmen , Humanos , Masculino , Metabolismo dos Lipídeos/genética , Astenozoospermia/genética , Ácidos Graxos Dessaturases/genética , Oligospermia/genética , Infertilidade Masculina/genética , Alelos , Adulto , Contagem de Espermatozoides , Fatores de Risco , Espermatozoides/metabolismo
16.
Hum Brain Mapp ; 44(9): 3859-3872, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37086449

RESUMO

In real life, it is not unusual that we face potential threats (i.e., physical stimuli and environments that may cause harm or danger) with other individuals together, yet it remains largely unknown how threat-induced anxious feelings influence prosocial behaviors such as resource sharing. In this study, we investigated this question by combining functional magnetic resonance imaging and a novel paradigm. Together with an anonymous partner, each participant faced the possibility of receiving a 10-s noise administration, which had a low or high probability to be a threat (i.e., the intensity of noise can induce a high level of unpleasantness). Each participant first reported her/his immediate feeling of anxiety about the current situation (being threatened by the unpleasant noise), then decided how to split a number of resources (which could relieve the noise) between her/him and the partner. Behavioral results revealed that the participants showed a selfish bias in the threat conditions than in the safe conditions, and that self-reported anxiety feeling significantly predicted this bias. Functional magnetic resonance imaging results revealed that: (1) the activation level of the anterior insula was correlated with self-reported anxiety and (2) the connectivity between the anterior insula and the temporoparietal junction was sensitive to the modulating effect of anxiety on the selfish bias. These findings indicate the neural correlates of the association between threat-induced anxiety and prosocial tendencies in social interactions.


Assuntos
Transtornos de Ansiedade , Ansiedade , Humanos , Masculino , Feminino , Ansiedade/diagnóstico por imagem , Emoções/fisiologia , Autorrelato , Imageamento por Ressonância Magnética/métodos
17.
Hum Brain Mapp ; 44(10): 4040-4051, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37146003

RESUMO

The cognitive and behavioral development of children and adolescents is closely related to the maturation of brain morphology. Although the trajectory of brain development has been depicted in detail, the underlying biological mechanism of normal cortical morphological development in childhood and adolescence remains unclear. By combining the Allen Human Brain Atlas dataset with two single-site magnetic resonance imaging data including 427 and 733 subjects from China and the United States, respectively, we performed partial least squares regression and enrichment analysis to explore the relationship between the gene transcriptional expression and the development of cortical thickness in childhood and adolescence. We found that the spatial model of normal cortical thinning during childhood and adolescence is associated with genes expressed predominantly in astrocytes, microglia, excitatory and inhibitory neurons. Top cortical development-related genes are enriched for energy-related and DNA-related terms and are associated with psychological and cognitive disorders. Interestingly, there is a great deal of similarity between the findings derived from the two single-site datasets. This fills the gap between early cortical development and transcriptomes, which promotes an integrative understanding of the potential biological neural mechanisms.


Assuntos
Córtex Cerebral , Afinamento Cortical Cerebral , Criança , Humanos , Adolescente , Córtex Cerebral/patologia , Afinamento Cortical Cerebral/patologia , Encéfalo , Neurônios , Imageamento por Ressonância Magnética/métodos
18.
Genome Res ; 30(5): 697-710, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32277013

RESUMO

Aging varies among individuals due to both genetics and environment, but the underlying molecular mechanisms remain largely unknown. Using a highly recombined Saccharomyces cerevisiae population, we found 30 distinct quantitative trait loci (QTLs) that control chronological life span (CLS) in calorie-rich and calorie-restricted environments and under rapamycin exposure. Calorie restriction and rapamycin extended life span in virtually all genotypes but through different genetic variants. We tracked the two major QTLs to the cell wall glycoprotein genes FLO11 and HPF1 We found that massive expansion of intragenic tandem repeats within the N-terminal domain of HPF1 was sufficient to cause pronounced life span shortening. Life span impairment by HPF1 was buffered by rapamycin but not by calorie restriction. The HPF1 repeat expansion shifted yeast cells from a sedentary to a buoyant state, thereby increasing their exposure to surrounding oxygen. The higher oxygenation altered methionine, lipid, and purine metabolism, and inhibited quiescence, which explains the life span shortening. We conclude that fast-evolving intragenic repeat expansions can fundamentally change the relationship between cells and their environment with profound effects on cellular lifestyle and longevity.


Assuntos
Expansão das Repetições de DNA , Proteínas de Saccharomyces cerevisiae/genética , Parede Celular , Genes Fúngicos , Metabolismo dos Lipídeos , Glicoproteínas de Membrana/genética , Metionina/metabolismo , Purinas/metabolismo , Locos de Características Quantitativas , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Sirolimo/farmacologia
19.
Opt Express ; 31(6): 9981-9995, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37157561

RESUMO

For integral stereo imaging systems based on lens arrays, the cross-mixing of erroneous light rays between adjacent lenses seriously affects the quality of the reconstructed light field. In this paper, we proposed a light field reconstruction method based on the human eye viewing mechanism, which incorporates simplified human eye imaging into the integral imaging system. First, the light field model for specified viewpoint is established, and the distribution of the light source for each viewpoint is accurately calculated for the EIA generation algorithm of fixed viewpoint. Second, according to the ray tracing algorithm in this paper, non-overlapping EIA based on the human eye viewing mechanism is designed to suppress the amount of crosstalk rays fundamentally. The actual viewing clarity is improved with the same reconstructed resolution. Experimental results verify the effectiveness of the proposed method. The SSIM value is higher than 0.93, which verifies that the viewing angle range is increased to 62°.


Assuntos
Imageamento Tridimensional , Lentes , Humanos , Imageamento Tridimensional/métodos , Algoritmos
20.
J Neurol Neurosurg Psychiatry ; 94(8): 605-613, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37225405

RESUMO

To explore the autoimmune response and outcome in the central nervous system (CNS) at the onset of viral infection and correlation between autoantibodies and viruses. METHODS: A retrospective observational study was conducted in 121 patients (2016-2021) with a CNS viral infection confirmed via cerebrospinal fluid (CSF) next-generation sequencing (cohort A). Their clinical information was analysed and CSF samples were screened for autoantibodies against monkey cerebellum by tissue-based assay. In situ hybridisation was used to detect Epstein-Barr virus (EBV) in brain tissue of 8 patients with glial fibrillar acidic protein (GFAP)-IgG and nasopharyngeal carcinoma tissue of 2 patients with GFAP-IgG as control (cohort B). RESULTS: Among cohort A (male:female=79:42; median age: 42 (14-78) years old), 61 (50.4%) participants had detectable autoantibodies in CSF. Compared with other viruses, EBV increased the odds of having GFAP-IgG (OR 18.22, 95% CI 6.54 to 50.77, p<0.001). In cohort B, EBV was found in the brain tissue from two of eight (25.0%) patients with GFAP-IgG. Autoantibody-positive patients had a higher CSF protein level (median: 1126.00 (281.00-5352.00) vs 700.00 (76.70-2899.00), p<0.001), lower CSF chloride level (mean: 119.80±6.24 vs 122.84±5.26, p=0.005), lower ratios of CSF-glucose/serum-glucose (median: 0.50[0.13-0.94] vs 0.60[0.26-1.23], p=0.003), more meningitis (26/61 (42.6%) vs 12/60 (20.0%), p=0.007) and higher follow-up modified Rankin Scale scores (1 (0-6) vs 0 (0-3), p=0.037) compared with antibody-negative patients. A Kaplan-Meier analysis revealed that autoantibody-positive patients experienced significantly worse outcomes (p=0.031). CONCLUSIONS: Autoimmune responses are found at the onset of viral encephalitis. EBV in the CNS increases the risk for autoimmunity to GFAP.


Assuntos
Encefalite , Infecções por Vírus Epstein-Barr , Masculino , Humanos , Feminino , Autoimunidade , Estudos Retrospectivos , Herpesvirus Humano 4 , Autoanticorpos , Imunoglobulina G
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