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1.
Proc Natl Acad Sci U S A ; 120(5): e2214684120, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36693099

RESUMO

Embryo implantation, a crucial step in human reproduction, is tightly controlled by estrogen and progesterone (P4) via estrogen receptor alpha and progesterone receptor (PGR), respectively. Here, we report that N6-methyladenosine (m6A), the most abundant mRNA modification in eukaryotes, plays an essential role in embryo implantation through the maintenance of P4 signaling. Conditional deletion of methyltransferase-like 3 (Mettl3), encoding the m6A writer METTL3, in the female reproductive tract using a Cre mouse line with Pgr promoter (Pgr-Cre) resulted in complete implantation failure due to pre-implantation embryo loss and defective uterine receptivity. Moreover, the uterus of Mettl3 null mice failed to respond to artificial decidualization. We further found that Mettl3 deletion was accompanied by a marked decrease in PGR protein expression. Mechanistically, we found that Pgr mRNA is a direct target for METTL3-mediated m6A modification. A luciferase assay revealed that the m6A modification in the 5' untranslated region (5'-UTR) of Pgr mRNA enhances PGR protein translation efficiency in a YTHDF1-dependent manner. Finally, we demonstrated that METTL3 is required for human endometrial stromal cell decidualization in vitro and that the METTL3-PGR axis is conserved between mice and humans. In summary, this study provides evidence that METTL3 is essential for normal P4 signaling during embryo implantation via m6A-mediated translation control of Pgr mRNA.


Assuntos
Progesterona , Receptores de Progesterona , Feminino , Camundongos , Humanos , Animais , Progesterona/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Implantação do Embrião/genética , Útero/metabolismo , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos Knockout , RNA Mensageiro/metabolismo
2.
Bioinformatics ; 40(2)2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38305428

RESUMO

MOTIVATION: 5-Methylcytosine (5mC), a fundamental element of DNA methylation in eukaryotes, plays a vital role in gene expression regulation, embryonic development, and other biological processes. Although several computational methods have been proposed for detecting the base modifications in DNA like 5mC sites from Nanopore sequencing data, they face challenges including sensitivity to noise, and ignoring the imbalanced distribution of methylation sites in real-world scenarios. RESULTS: Here, we develop NanoCon, a deep hybrid network coupled with contrastive learning strategy to detect 5mC methylation sites from Nanopore reads. In particular, we adopted a contrastive learning module to alleviate the issues caused by imbalanced data distribution in nanopore sequencing, offering a more accurate and robust detection of 5mC sites. Evaluation results demonstrate that NanoCon outperforms existing methods, highlighting its potential as a valuable tool in genomic sequencing and methylation prediction. In addition, we also verified the effectiveness of our representation learning ability on two datasets by visualizing the dimension reduction of the features of methylation and nonmethylation sites from our NanoCon. Furthermore, cross-species and cross-5mC methylation motifs experiments indicated the robustness and the ability to perform transfer learning of our model. We hope this work can contribute to the community by providing a powerful and reliable solution for 5mC site detection in genomic studies. AVAILABILITY AND IMPLEMENTATION: The project code is available at https://github.com/Challis-yin/NanoCon.


Assuntos
Nanoporos , Metilação de DNA , Genômica , Genoma , DNA
3.
Plant Cell ; 34(5): 1768-1783, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35099562

RESUMO

Perception of pathogen-associated molecular patterns (PAMPs) by plant cell surface-localized pattern-recognition receptors (PRRs) triggers the first line of plant innate immunity. In Arabidopsis thaliana, the receptor-like cytoplasmic kinase BRASSINOSTEROID-SIGNALING KINASE1 (BSK1) physically associates with PRR FLAGELLIN SENSING2 and plays an important role in defense against multiple pathogens. However, how BSK1 transduces signals to activate downstream immune responses remains elusive. Previously, through whole-genome phosphorylation analysis using mass spectrometry, we showed that phosphorylation of the mitogen-activated protein kinase (MAPK) MPK15 was affected in the bsk1 mutant compared with the wild-type plants. Here, we demonstrated that MPK15 is important for powdery mildew fungal resistance. PAMPs and fungal pathogens significantly induced the phosphorylation of MPK15 Ser-511, a key phosphorylation site critical for the functions of MPK15 in powdery mildew resistance. BSK1 physically associates with MPK15 and is required for basal and pathogen-induced MPK15 Ser-511 phosphorylation, which contributes to BSK1-mediated fungal resistance. Taken together, our data identified MPK15 as a player in plant defense against powdery mildew fungi and showed that BSK1 promotes fungal resistance in part by enhancing MPK15 Ser-511 phosphorylation. These results uncovered a mechanism of BSK1-mediated disease resistance and provided new insight into the role of MAPK phosphorylation in plant immunity.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Brassinosteroides/metabolismo , Resistência à Doença/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Moléculas com Motivos Associados a Patógenos/metabolismo , Fosforilação , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética , Proteínas Serina-Treonina Quinases/genética
4.
Plant Cell ; 34(9): 3425-3442, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-35642941

RESUMO

Plants manage the high cost of immunity activation by suppressing the expression of defense genes during normal growth and rapidly switching them on upon pathogen invasion. TGAs are key transcription factors controlling the expression of defense genes. However, how TGAs function, especially in monocot plants like rice with continuously high levels of endogenous salicylic acid (SA) remains elusive. In this study, we characterized the role of OsTGA5 as a negative regulator of rice resistance against blast fungus by transcriptionally repressing the expression of various defense-related genes. Moreover, OsTGA5 repressed PTI responses and the accumulation of endogenous SA. Importantly, we showed that the nucleus-localized casein kinase II (CK2) complex interacts with and phosphorylates OsTGA5 on Ser-32, which reduces the affinity of OsTGA5 for the JIOsPR10 promoter, thereby alleviating the repression of JIOsPR10 transcription and increasing rice resistance. Furthermore, the in vivo phosphorylation of OsTGA5 Ser-32 was enhanced by blast fungus infection. The CK2 α subunit, depending on its kinase activity, positively regulated rice defense against blast fungus. Taken together, our results provide a mechanism for the role of OsTGA5 in negatively regulating the transcription of defense-related genes in rice and the repressive switch imposed by nuclear CK2-mediated phosphorylation during blast fungus invasion.


Assuntos
Magnaporthe , Oryza , Caseína Quinase II , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Fosforilação , Doenças das Plantas , Proteínas de Plantas , Ácido Salicílico , Transcrição Gênica
5.
Proc Natl Acad Sci U S A ; 119(19): e2201288119, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35507870

RESUMO

African swine fever virus (ASFV) is the causative agent of African swine fever, a highly contagious and usually fatal disease in pigs. The pathogenesis of ASFV infection has not been clearly elucidated. Here, we used single-cell RNA-sequencing technology to survey the transcriptomic landscape of ASFV-infected primary porcine alveolar macrophages. The temporal dynamic analysis of viral genes revealed increased expression of viral transmembrane genes. Molecular characteristics in the ASFV-exposed cells exhibited the activation of antiviral signaling pathways with increased expression levels of interferon-stimulated genes and inflammatory- and cytokine-related genes. By comparing infected cells with unexposed cells, we showed that the unfolded protein response (UPR) pathway was activated in low viral load cells, while the expression level of UPR-related genes in high viral load cells was less than that in unexposed cells. Cells infected with various viral loads showed signature transcriptomic changes at the median progression of infection. Within the infected cells, differential expression analysis and coregulated virus­host analysis both demonstrated that ASFV promoted metabolic pathways but inhibited interferon and UPR signaling, implying the regulation pathway of viral replication in host cells. Furthermore, our results revealed that the cell apoptosis pathway was activated upon ASFV infection. Mechanistically, the production of tumor necrosis factor alpha (TNF-α) induced by ASFV infection is necessary for cell apoptosis, highlighting the importance of TNF-α in ASFV pathogenesis. Collectively, the data provide insights into the comprehensive host responses and complex virus­host interactions during ASFV infection, which may instruct future research on antiviral strategies.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Vírus da Febre Suína Africana/genética , Animais , Antivirais/metabolismo , Perfilação da Expressão Gênica , Macrófagos/metabolismo , Suínos , Replicação Viral/fisiologia
6.
J Am Chem Soc ; 146(11): 7616-7627, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38446772

RESUMO

Natural products and their analogues are significant sources of therapeutic lead compounds. However, synthetic strategies for generating large collections of these molecules remain a significant challenge. The most difficult step in their synthesis is the design of a common intermediate that can be easily transformed into natural products belonging to different families. This study demonstrates the evolution of synthetic tactics designed to assemble the functionalized piperidines present in indole alkaloids from a common intermediate. More importantly, we also report a previously unknown Ir- and Er-catalyzed dehydrogenative spirocyclization reaction that enables direct access to spirocyclic oxindole alkaloids. As a practical application, the asymmetric total syntheses of 29 natural alkaloids belonging to different families were accomplished by following a uniform synthetic route. The proposed methodology extends the capability of the iridium-catalyzed dehydrogenative coupling reaction to the realm of indole-alkaloid synthesis and provides new opportunities for the efficient preparation of natural product-like molecules.


Assuntos
Alcaloides , Produtos Biológicos , Humanos , Estereoisomerismo , Alcaloides Indólicos , Oxindóis
7.
Anal Chem ; 96(1): 179-187, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38100653

RESUMO

Achieving accurate detection of different speciations of heavy metal ions (HMIs) in an aqueous solution is an urgent problem due to the different bioavailabilities and physiological toxicity. Herein, we nominated a novel strategy to detect HCrO4- and Cr(OH)2+ at a trace level via the electrochemical sensitive surface constructed by Co3O4-rGO modified with amino and carboxyl groups, which revealed that the interactions between distinct functional groups and different oxygen-containing groups of target ions are conducive to the susceptible and anti-interference detection. The detection sensitivities of 19.46 counts µg-1 L for HCrO4- and 13.44 counts µg-1 L for Cr(OH)2+ were obtained under optimal conditions, while the limits of detection were 0.10 and 0.12 µg L-1, respectively. Satisfactory anti-interference and actual water sample analysis results were obtained. A series of advanced optical techniques like X-ray photoelectron spectroscopy, X-ray absorption near-edge structure technology, and density functional theory calculations under an electric field demonstrated that chemical interactions between groups contribute more to the fixation of target ions than electrical attraction alone. The presence of oxygen-containing groups distinct from simple ionic forms was a critical factor in the selectivity and anti-interference detection. Furthermore, the valence cycle of Co(II)/(III) synergistically boosted the detection performance. This research provides a promising tactic from the microscopic perspective of groups' interactions to accomplish the precise speciation analysis of HMIs in the water environment.

8.
Anal Chem ; 96(13): 5232-5241, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38447030

RESUMO

Although utilizing nanomaterial-modified electrodes for lead ion detection has achieved great success, most of them are carried out under acidic conditions and ignore the variation of Pb(II) speciation at different pH conditions, leading to the potential inaccuracy of Pb(II) detection in a neutral natural water environment. Thus, designing a novel catalyst with high accuracy for the detection of various forms of the total amount of Pb(II) (Pb2+ and Pb(OH)+) in neutral waters is significant. Herein, Pt nanoclusters (Pt NCs) were elaborately constructed and stabilized on the Co single-atom-doped g-C3N4 with abundant N vacancies (Pt NCs/VN-C3N4), which achieved the ultrasensitive detection (102.16 µM µA-1) of Pb(II) in neutral conditions. The dynamic simulation and theoretical calculations reveal that the parallel deposition of Pb2+ and Pb(OH)+ occurs on the electrode surface modified by Pt NCs/VN-C3N4, and the current peaks of Pb(II) are cocontributed by Pb2+ and Pb(OH)+ species. An "electron inverse" phenomenon in Pt NCs/VN-C3N4 from the VN-C3N4 substrate to Pt NCs endows Pt NCs in an electron-rich state, serving as active centers to promote rapid and efficient reduction for both Pb2+ and Pb(OH)+, facilitating the accurate detection of the total amount of Pb(II) in all forms in the actual water environment.

9.
New Phytol ; 241(1): 363-377, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37786257

RESUMO

Nuclear pore complex (NPC) is composed of multiple nucleoporins (Nups). A plethora of studies have highlighted the significance of NPC in plant immunity. However, the specific roles of individual Nups are poorly understood. NUCLEAR PORE ANCHOR (NUA) is a component of NPC. Loss of NUA leads to an increase in SUMO conjugates and pleiotropic developmental defects in Arabidopsis thaliana. Herein, we revealed that NUA is required for plant defense against multiple pathogens. NUCLEAR PORE ANCHOR associates with the transcriptional corepressor TOPLESS-RELATED1 (TPR1) and contributes to TPR1 deSUMOylation. Significantly, NUA-interacting protein EARLY IN SHORT DAYS 4 (ESD4), a SUMO protease, specifically deSUMOylates TPR1. It has been previously established that the SUMO E3 ligase SAP AND MIZ1 DOMAIN-CONTAINING LIGASE 1 (SIZ1)-mediated SUMOylation of TPR1 represses the immune-related function of TPR1. Consistent with this notion, the hyper-SUMOylated TPR1 in nua-3 leads to upregulated expression of TPR1 target genes and compromised TPR1-mediated disease resistance. Taken together, our work uncovers a mechanism by which NUA positively regulates plant defense responses by coordination with ESD4 to deSUMOylate TPR1. Our findings, together with previous studies, reveal a regulatory module in which SIZ1 and NUA/ESD4 control the homeostasis of TPR1 SUMOylation to maintain proper immune output.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Imunidade Vegetal , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Ligases/metabolismo , Poro Nuclear/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Sumoilação
10.
Langmuir ; 40(20): 10759-10768, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38712734

RESUMO

Bouncing dynamics of a trailing drop off-center impacting a leading drop with varying time intervals and Weber numbers are investigated experimentally. Whether the trailing drop impacts during the spreading or receding process of the leading drop is determined by the time interval. For a short time interval of 0.15 ≤ Δt* ≤ 0.66, the trailing drop impacts during the spreading of the leading drop, and the drops completely coalesce and rebound; for a large time interval of 0.66 < Δt* ≤ 2.21, the trailing drop impacts during the receding process, and the drops partially coalesce and rebound. Whether the trailing drop directly impacts the surface or the liquid film of the leading drop is determined by the Weber number. The trailing drop impacts the surface directly at moderate Weber numbers of 16.22 ≤ We ≤ 45.42, while it impacts the liquid film at large Weber numbers of 45.42 < We ≤ 64.88. Intriguingly, when the trailing drop impacts the surface directly or the receding liquid film, the contact time increases linearly with the time interval but independent of the Weber number; when the trailing drop impacts the spreading liquid film, the contact time suddenly increases, showing that the force of the liquid film of the leading drop inhibits the receding of the trailing drop. Finally, a theoretical model of the contact time for the drops is established, which is suitable for different impact scenarios of the successive off-center impact. This study provides a quantitative relationship to calculate the contact time of drops successively impacting a superhydrophobic surface, facilitating the design of anti-icing surfaces.

11.
Anal Chem ; 95(7): 3666-3674, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36656141

RESUMO

Traditional nanomodified electrodes have made great achievements in electrochemical stripping voltammetry of sensing materials for As(III) detection. Moreover, the intermediate states are complicated to probe because of the ultrashort lifetime and complex reaction conditions of the electron transfer process in electroanalysis, which seriously hinder the identification of the actual active site. Herein, the intrinsic interaction of highly sensitive analytical behavior of nanomaterials is elucidated from the perspective of electronic structure through density functional theory (DFT) and gradient boosting regression (GBR). It is revealed that the atomic radius, d-band center (εd), and the largest coordinative TM-N bond length play a crucial role in regulating the arsenic reduction reaction (ARR) performance by the established ARR process for 27 sets of transition-metal single atoms supported on N-doped graphene. Furthermore, the database composed of filtered intrinsic electronic structural properties and the calculated descriptors of the central metal atom in TM-N4-Gra were also successfully extended to oxygen evolution reaction (OER) systems, which effectively verified the reliability of the whole approach. Generally, a multistep workflow is developed through GBR models combined with DFT for valid screening of sensing materials, which will effectively upgrade the traditional trial-and-error mode for electrochemical interface designing.

12.
Crit Rev Food Sci Nutr ; 63(16): 2738-2748, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34664530

RESUMO

Cultured meat (CM) has emerged as a breakthrough technology, which has the potential to minimise future negative impacts associated with the rapidly growing world population; such as serious environmental, sustainability, global public health, and animal welfare concerns. Recently numerous researchers in academia and companies have been putting significant efforts into scientific and translational development in this field. Since various pillars of CM manufacturing hold substantial translational potential, there has been a steady interest in filing patent applications globally in the past decade. For the first time, we have performed a patentometric analysis for cultured meat by highlighting the current patents landscape, determining prolific organisations and geographical locations active in the area, and identifying the overall outlook for the field. In total, > 190 patents published in the English language were collected from 1997 to 2020 for the analysis. Relevant data were extracted from the patents, including technology focus, country of origin, assignees, priority date, cooperative patent classification (CPC) code, to analyse the current patent landscape.


Assuntos
Alimento Processado , Produtos da Carne , Patentes como Assunto
13.
Methods ; 204: 126-131, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35231584

RESUMO

N6-methyladenine (6mA) in DNA, a type of DNA methylation in epigenetic modification, has attracted extensive attention in recent years. In order to improve our understanding of 6mA biological activities and mechanisms in plant genomes, we need to be able to accurately identify 6mA sites. Because traditional wet-lab experiments frequently necessitate a large amount of manpower and time, a plethora of computational methods, particularly machine learning, have emerged to achieve fast and accurate 6mA site prediction. Traditional machine learning methods, on the other hand, rely heavily on manual features and integrated learning to improve performance, resulting in a reliance on prior knowledge and a large model scale. Furthermore, many models are only trained and tested for one species, with no comparison of model generalization performance, resulting in models with limited practical usability. In order to increase the generalization capability of the model, we propose a lightweight structure predictor Plant6mA based on Transformer encoder. Based on results on independent test sets, our proposed Plant6mA has better generalization performance than the most advanced methods in predicting 6mA location in plant genomes. Plant6mA's MultiHead Attention mechanism effectively enhances its expressive ability by capturing potential biological information from multiple scales of the input sequence. Furthermore, we used a dimensionality reduction tool to visualize Plant6mA's training process and visually demonstrate the effectiveness of our model.


Assuntos
Metilação de DNA , Genoma de Planta , DNA , Metilação de DNA/genética , Epigênese Genética
14.
Clin Lab ; 69(7)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37436382

RESUMO

BACKGROUND: Hemophilus influenzae (Hi) is one of the major pediatric bacterial pneumonia pathogens that heavily threatens children's lives and global health. With widespread usage as first-line treatment, the prevalence of ß-lactam-resistant strains is increasing sharply. In order to treat Hi more effectively, a systematic study on the antibiotic resistance profiles, ß-lactamase-negative ampicillin-resistant (BLNAR) strains isolation rate, and potential BLNAR resistance mechanism in our region is needed. METHODS: This study analyzed antimicrobial susceptibility of Hi, and clinical data of Hi-infected patients retrospectively. BLNAR and ß-lactamase-positive ampicillin-clavulanate resistant strains (BLPACR) were confirmed by the Kirby-Bauer method and ß-lactamase test. ftsI gene in BLNAR was sequenced to find out whether resistance was induced by penicillin-binding protein mutation. Ampicillin susceptibility test with or without efflux pump inhibitors were done to assess efflux pump contribution in BLNAR. RT-PCR was performed to evaluate the efflux pump genes' transcription levels. RESULTS: A total of 2,561 Hi strains were isolated in our hospital from January 2016 to December 2019. Male to female ratio was 1.52:1. Median age was 10 months. Infant (< 3 years old) infection accounted for 83.72%. Hi resistance rates to sulfamethoxazole-trimethoprim, ampicillin, cefathiamidine, cefaclor, cefuroxime, cephalothin, amoxicillin-clavulanate, tetracycline, chloramphenicol, ofloxacin, cefotaxime, and rifampin were 84.28%, 78.01%, 49.80%, 41.98%, 36.58%, 33.64%, 4.55%, 4.1%, 3.37%, 1.77%, 0.99%, and 0.12%, respectively, while 1.33% were BLNAR. BLNARs were classified into four groups by mutation patterns in ftsI gene and most strains were divided to Group Ⅲ/Ⅲ-like. EmrB, ydeA and norM transcription levels in some ampicillin-resistant strains were higher than their sensitive counterparts. CONCLUSIONS: Ampicillin is not sufficiently effective as a first-line Hi infection treatment. However, ampicillin-clavulanate and cefotaxime may be a better choice. Efflux pumps, emrB, ydeA and norM play roles in the high resistance to ampicillin.


Assuntos
Infecções por Haemophilus , Haemophilus influenzae , Lactente , Criança , Humanos , Masculino , Feminino , Pré-Escolar , Haemophilus influenzae/genética , Estudos Retrospectivos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Ampicilina , Resistência Microbiana a Medicamentos , Infecções por Haemophilus/epidemiologia , Infecções por Haemophilus/microbiologia , beta-Lactamases/genética , beta-Lactamases/metabolismo , Cefotaxima/farmacologia , Ácido Clavulânico/farmacologia
15.
BMC Pregnancy Childbirth ; 23(1): 355, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37194003

RESUMO

BACKGROUND: Vascular rings (VRs) exhibit complex and diverse forms that are difficult to conceptualize using traditional two-dimensional (2D) schematic. Inexperienced medical students and parents who lack a medical technology background face significant challenges in understanding VRs. The purpose of this research is to develop three-dimensional (3D) printing models of VRs to provide new technical imaging support for medical education and parental consultation. METHODS: This study included 42 fetuses diagnosed as VRs. Foetal echocardiography, modeling and 3D printing were performed, and the dimensional accuracy of models was analyzed. The value of 3D printing in the teaching of VRs was analyzed based on comparing the test results before and after the teaching intervention of 48 medical students and the satisfaction survey. A brief survey was conducted to 40 parents to assess the value of the 3D printed model in prenatal consultations. RESULTS: Forty models of VRs were successfully obtained, which reproduced the anatomical shape of the VRs space with high dimensional accuracy. No differences in the prelecture test results were noted between the 3D printing group and the 2D image group. After the lecture, the knowledge of both groups improved, but the postlecture score and the change in the prelecture versus postlecture score were greater in the 3D printing group, and the subjective satisfaction survey feedback in the 3D printing group was also better (P < 0.05). Similar results were observed from the parental questionnaire, the vast majority of parents have an enthusiastic and positive attitude towards the use of 3D printed models and suggest using them in future prenatal consultations. CONCLUSIONS: Three-dimensional printing technology providing a new tool for effectively displaying different types of foetal VRs. This tool helps physicians and families understand the complex structure of foetal great vessels, positively impacting medical instruction and prenatal counselling.


Assuntos
Feto , Impressão Tridimensional , Anel Vascular , Feminino , Humanos , Gravidez , Educação Médica/métodos , Estudos de Viabilidade , Feto/diagnóstico por imagem
16.
Arch Environ Contam Toxicol ; 84(2): 284-298, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36737498

RESUMO

Hydraulic fracturing technologies have been frequently utilized in the oil and gas industry as exploration and development efforts have progressed, resulting in a significant increase in the extraction of natural gas and petroleum from low-permeability reservoirs. However, hydraulic fracturing requires a large amount of freshwater, and the process results in the production of large volumes of flowback water along with natural gas. In this study, three tight sandstone gas wells were fractured in the Sulige gasfield (China), and a total of 103 flowback fluid samples were collected. The hydrochemical characteristics, water quality and sources of hydrochemical components in the flowback fluid were discussed. The results show that the flowback fluid is characterized by high salinity (Total dissolved solids (TDS) up to 38,268 mg/L, Cl- up to 24,000 mg/L), high concentrations of metal ions (e.g., Fe, Sr2+, Ba2+) and high chemical oxygen demand (COD). The flowback fluid is a complex mixture of fracturing fluid and formation water, and its composition is impacted by water-rock interactions that occur during hydraulic fracturing. The major contaminants include COD, Fe, Ba2+, Cl-, Mn and pH, which constitute a high risk of environmental pollution. Meanwhile, chemical elements such as K, Ba and Sr are unusually enriched in the flowback fluid, which has an excellent potential for recycle of chemical elements. The Sulige gasfield's flowback fluid recovery methods and treatment scenarios were discussed, taking into consideration the pollution and resource characteristics of the flowback fluid. Options for dealing with the flowback fluid include deep well reinjection, reuse for making up fracturing fluid, recycling of chemical elements and diverse reuse of flowback water. This research offers guidance for managing the fracturing flowback fluid in unconventional oil and gas fields.


Assuntos
Gás Natural , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Águas Residuárias , Campos de Petróleo e Gás , China
17.
Sheng Li Xue Bao ; 75(3): 429-438, 2023 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-37340651

RESUMO

It has been well documented that exercise can improve bone metabolism, promote bone growth and development, and alleviate bone loss. MicroRNAs (miRNAs) are widely involved in the proliferation and differentiation of bone marrow mesenchymal stem cells, osteoblasts, osteoclasts and other bone tissue cells, and regulation of balance between bone formation and bone resorption by targeting osteogenic factors or bone resorption factors. Thus miRNAs play an important role in the regulation of bone metabolism. Recently, regulation of miRNAs are shown to be one of the ways by which exercise or mechanical stress promotes the positive balance of bone metabolism. Exercise induces changes of miRNAs expression in bone tissue and regulates the expression of related osteogenic factors or bone resorption factors, to further strengthen the osteogenic effect of exercise. This review summarizes relevant studies on the mechanism whereby exercise regulates bone metabolism via miRNAs, providing a theoretical basis for osteoporosis prevention and treatment with exercise.


Assuntos
Reabsorção Óssea , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Osteogênese/genética , Diferenciação Celular , Osteoblastos , Reabsorção Óssea/metabolismo
18.
Can J Infect Dis Med Microbiol ; 2023: 8508975, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124122

RESUMO

Objective: This study aims to assess the effectiveness of surveillance inspections conducted by the provincial health committee in Quanzhou city during a COVID-19 outbreak in reducing false-positive results in SARS-CoV-2 RT-PCR assays. Method: The team conducted on-site inspections of laboratories that participated in mass screening, recording any violations of rules. Results: The positive cases in five rounds of mass screening were 23, 173, and 4 in Licheng District, Fengze District, and Luojang District, respectively. The false-positive rates in the five rounds of mass screening were 0.0099%, 0.0063%, 0.0018%, 0.0006%, and 0%, respectively. The study also recorded that the number of violations in the seven selected laboratories was 36, 68, 69, 42, 60, 54 and 47. The corresponding false-positive rates were 0.0012%, 0.0060%, 0.0082%, 0.0032%, 0.0060%, 0.0027%, and 0.0021%, respectively. The study found a positive correlation between false-positive rates and the number of violations (r = 0.905, P=0.005), and an inverse correlation between false-positive rates and the frequency of surveillance inspections (r = -0.950, P < 0.001). Conclusion: Daily surveillance inspection in laboratories can remind laboratories to strictly comply with standard procedures, focus on laboratory quality control, and reduce the occurrence of false-positive cases in SARS-CoV-2 nucleic acid tests to some extent. This study recommends that government decision-making departments establish policies and arrange experts to conduct daily surveillance inspections to improve laboratory quality control.

19.
Angew Chem Int Ed Engl ; 62(36): e202306822, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37468435

RESUMO

We propose an effective highest occupied d-orbital modulation strategy engendered by breaking the coordination symmetry of sites in the atomically precise Cu nanocluster (NC) to switch the product of CO2 electroreduction from HCOOH/CO to higher-valued hydrocarbons. An atomically well-defined Cu6 NC with symmetry-broken Cu-S2 N1 active sites (named Cu6 (MBD)6 , MBD=2-mercaptobenzimidazole) was designed and synthesized by a judicious choice of ligand containing both S and N coordination atoms. Different from the previously reported high HCOOH selectivity of Cu NCs with Cu-S3 sites, the Cu6 (MBD)6 with Cu-S2 N1 coordination structure shows a high Faradaic efficiency toward hydrocarbons of 65.5 % at -1.4 V versus the reversible hydrogen electrode (including 42.5 % CH4 and 23 % C2 H4 ), with the hydrocarbons partial current density of -183.4 mA cm-2 . Theoretical calculations reveal that the symmetry-broken Cu-S2 N1 sites can rearrange the Cu 3d orbitals with d x 2 - y 2 ${d_{x^2 - y^2 } }$ as the highest occupied d-orbital, thus favoring the generation of key intermediate *COOH instead of *OCHO to favor *CO formation, followed by hydrogenation and/or C-C coupling to produce hydrocarbons. This is the first attempt to regulate the coordination mode of Cu atom in Cu NCs for hydrocarbons generation, and provides new inspiration for designing atomically precise NCs for efficient CO2 RR towards highly-valued products.

20.
Physiol Genomics ; 54(6): 187-195, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35468005

RESUMO

In most mammalian species, the testis descends from the abdomen into the scrotum during fetal or neonatal life. The failure of testicular descent, a pathological condition known as cryptorchidism, has long been the subject of scientific interest in a wide range of fields, including medicine, developmental biology, and evolutionary biology. In this study, we analyzed global gene expression changes associated with experimental cryptorchidism in mice by using RNA-seq. A total of 453 differentially expressed genes were identified, of which 236 genes were upregulated, and 217 genes were downregulated. Gene ontology, pathway, and gene network analysis highlighted the activation of inflammatory response in experimental cryptorchidism. By examining the promoter regions of differentially expressed genes, we identified 12 causal transcription factors. In addition, we also induced experimental cryptorchidism in two cynomolgus monkeys and performed RNA-seq. A cross-species comparison was performed at the gene expression level. Our study provides a valuable resource for further understanding the molecular mechanisms of cryptorchidism in mammals.


Assuntos
Criptorquidismo , Animais , Criptorquidismo/genética , Criptorquidismo/metabolismo , Criptorquidismo/patologia , Perfilação da Expressão Gênica , Humanos , Macaca fascicularis/genética , Masculino , Mamíferos/genética , Testículo/metabolismo , Transcriptoma/genética
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