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1.
Nucleic Acids Res ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39445805

RESUMO

The precise role of the highly variable coronavirus S protein in modulating innate immune responses remains unclear. In this study, we demonstrated that the mutant strain of swine coronavirus porcine enteric diarrhea virus induced significantly lower levels of double-stranded RNA (dsRNA) accumulation, inhibited protein kinase R (PKR) activation and suppressed stress granule (SG) formation compared with the classical strain. The 29th amino acid at N-terminus of S was identified as the key functional site for regulation of SG formation, and found that mutant S inhibited PKR phosphorylation and SG formation by upregulating adenosine deaminase acting on RNA 1 (ADAR1)-p150. Notably, the Zα domain of ADAR1-p150 was essential for inhibiting SG formation. Upregulation of ADAR1-p150 also reduced accumulation of dsRNA depending on its RNA editing function. Virus rescue confirmed that the mutant carrying a substitution at amino acid 29 failed to induce ADAR1-p150, leading to dsRNA accumulation, PKR activation and SG formation. Interestingly, the latest severe acute respiratory syndrome coronavirus-2 strains exhibit a novel 25PPA27 deletion at N-terminus of S that was also shown to lead to altered ADAR1-p150 expression and SG inhibition. The transcription factor TCF7L2 was identified as a player in S-mediated transcriptional enhancement of ADAR1-p150. This study is the first to clarify the crucial role of N-terminus of S in immune regulation of coronaviruses.

2.
Nat Commun ; 15(1): 9031, 2024 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-39424819

RESUMO

Edge states in topological systems have attracted great interest due to their robustness and linear dispersions. Here a superconducting-proximitized edge interferometer is engineered on a topological insulator Ta2Pd3Te5 with asymmetric edges to realize the interfering Josephson diode effect (JDE), which hosts many advantages, such as the high efficiency as much as 73% at tiny applied magnetic fields with an ultra-low switching power around picowatt. As an important element to induce such JDE, the second-order harmonic in the current-phase relation is also experimentally confirmed by half-integer Shapiro steps. The interfering JDE is also accompanied by the antisymmetric second harmonic transport, which indicates the corresponding asymmetry in the interferometer, as well as the polarity of JDE. This edge interferometer offers an effective method to enhance the performance of JDE, and boosts great potential applications for future superconducting quantum devices.

3.
Zookeys ; 1213: 267-288, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39372276

RESUMO

The complete mitochondrial genomes of Tipula (Pterelachisus) cinereocincta mesacantha Alexander, 1934, T. (P.) legalis Alexander, 1933, T. (P.) varipennis Meigen, 1818, and T. (P.) yasumatsuana Alexander, 1954 are reported, three of them being sequenced for the first time. The mitochondrial genome lengths of the four species are 15,907 bp, 15,625 bp, 15,772 bp, and 15,735 bp, respectively. All genomes exhibit a high AT base composition, with A + T content of 76.7%, 75.0%, 77.8%, and 75.4%, respectively. The newly reported mitogenomes herein show a general similarity in overall structure, gene order, base composition, and nucleotide content to those of the previously studied species within the family Tipulidae. Phylogenetic analyses were conducted to investigate the relationships within Tipulidae, using both Maximum Likelihood and Bayesian Inference approaches. The results show that the four target species of the subgenus T. (Pterelachisus) basically form a monophyletic group within Tipulidae, clustering with species of the Tipula subgenera T. (Lunatipula), T. (Vestiplex), and T. (Formotipula); however, the genus Tipula is not monophyletic. Moreover, neither the tipulid subfamily Tipulinae nor the family Limoniidae is supported to be a monophyletic group. The monophyly of the family Tipulidae, and the sister relationship between Tipulidae and Cylindrotomidae are reconfirmed. These research findings could contribute to deep insights into the systematic and evolutionary patterns of crane flies.

5.
J Virol ; 98(10): e0130924, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39254314

RESUMO

Variant Porcine epidemic diarrhea virus (PEDV), which causes diarrhea and high mortality in piglets, has become a major pathogen, and co-epidemics of different subtypes of the virus have become a very thorny problem for the clinical prevention and control of PEDV. However, cross-protection between epidemic G2a and G2b subtype strains has not been observed, and there is currently no vaccine against both G2a and G2b strains. In this study, we demonstrate the low cross-protection between G2a and G2b strains with piglet immunization and challenge tests. The trimeric full-length S proteins of G2a and G2b variants were purified and a bivalent subunit vaccine against PEDV G2a/G2b-S was developed. In active and passive immune protection tests, the bivalent subunit vaccine produced high neutralizing antibody titers and S-specific immunoglobulin G (IgG) and IgA titers against both the G2a and G2b strains in piglets and sows. In the attack phase of the viruses, the clinical symptoms and microscopic lesions in the immunized groups were significantly alleviated. Importantly, the PEDV G2a/G2b-S bivalent subunit vaccine conferred effective passive immunity against PEDV G2a and G2b challenges in the form of colostrum-derived antibodies from the immunized sows. In conclusion, our data demonstrate the low cross-protection of PEDV epidemic G2a and G2b strains and show that the G2a/G2b-S bivalent subunit vaccine is protective against both G2a and G2b strains. It is therefore a candidate vaccine for PEDV prevention. IMPORTANCE: The detection rate of PEDV G2a subtype strains is currently increasing. Although commercial vaccines are available, most vaccines do not exert an ideal protective effect against these strains. Furthermore, there is no definitive research into the cross-protection between G2a and G2b strains, and no bivalent vaccine provides joint protection against both. Therefore, in this study, we investigated the cross-protection between PEDV G2a and G2b strains and designed a candidate bivalent subunit vaccine combining the trimeric S proteins of the G2a and G2b subtypes. We demonstrate that the cross-protection between strains G2a and G2b is poor and that this bivalent subunit vaccine protects piglets from viral attack by inducing both active and passive immunity. This study emphasizes the effectiveness of the PEDV G2a/G2b-S bivalent subunit vaccine and provides a feasible method for the development of efficient PEDV vaccines.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Infecções por Coronavirus , Proteção Cruzada , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Vacinas de Subunidades Antigênicas , Vacinas Virais , Vírus da Diarreia Epidêmica Suína/imunologia , Animais , Suínos , Proteção Cruzada/imunologia , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue , Vacinas de Subunidades Antigênicas/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Vacinas Virais/imunologia , Vacinas Virais/administração & dosagem , Chlorocebus aethiops , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Células Vero , Feminino , Glicoproteína da Espícula de Coronavírus/imunologia , Imunoglobulina A/imunologia
6.
Animals (Basel) ; 14(17)2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39272375

RESUMO

Cow milk possesses high nutritional value due to its rich array of beneficial fatty acids. It is important to understand the mechanisms involved in lipid metabolism in dairy cows. These mechanisms are driven by a complex molecular regulatory network. In addition, there are many regulatory factors involved in the process of fatty acid metabolism, including transcription factors and non-coding RNAs, amongst others. MicroRNAs (miRNAs) can regulate the expression of target genes and modulate various biological processes, including lipid metabolism. Specifically, miR-206 has been reported to impair lipid accumulation in nonruminant hepatocytes. However, the effects and regulatory mechanisms of miR-206 on lipid metabolism in bovine mammary cells remain unclear. In the present study, we investigated the effects of miR-206 on lipid-related genes and TAG accumulation. The direct downstream gene of miR-206 was subsequently determined via a dual-luciferase assay. Finally, the fatty acid content of bovine mammary epithelial cells (BMECs) upon ELOVL6 inhibition was examined. The results revealed that miR-206 overexpression significantly decreased triacylglycerol (TAG) concentration and abundances of the following: acetyl-coenzyme A carboxylase alpha (ACACA); fatty acid synthase (FASN); sterol regulatory element binding transcription factor 1 (SREBF1); diacylglycerol acyltransferase 1 (DGAT1); 1-acylglycerol-3-phosphate O-acyltransferase 6 (AGPAT6); lipin 1 (LPIN1); and fatty acid elongase 6 (ELOVL6). Overexpression of miR-206 was also associated with an increase in patatin-like phospholipase domain-containing 2 (PNPLA2), while inhibition of miR-206 promoted milk fat metabolism in vitro. In addition, we found that ELOVL6 is a direct target gene of miR-206 through mutation of the binding site. Furthermore, ELOVL6 intervention significantly decreased the TAG levels and elongation indexes of C16:0 and C16:1n-7 in BMECs. Finally, ELOVL6 siRNA partially alleviated the increased TAG accumulation caused by miR-206 inhibition. In summary, we found that miR-206 inhibits milk fatty acid synthesis and lipid accumulation by targeting ELOVL6 in BMECs. The results presented in this paper may contribute to the development of strategies for enhancing the quality of cow milk and its beneficial fatty acids, from the perspective of miRNA-mRNA networks.

7.
BMC Musculoskelet Disord ; 25(1): 730, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39267026

RESUMO

BACKGROUND: Total knee arthroplasty (TKA) successfully alleviates pain from knee osteoarthritis, but muscle strength and function are reduced for a long period postoperatively. Postoperative active resistance exercise may play a relevant role. PURPOSE: To systematically evaluate effects of lower-limb active resistance exercise (ARE) on mobility, physical function, muscle strength and pain intensity in patients with TKA. METHODS: A search was conducted in PubMed, EMBASE, and Cochrane Library databases from inception to September 2023. Only randomized controlled trials (RCTs) that compared the effects of ARE and no intervention or other rehabilitation program without PRE were included. The outcome variables were mobility (Maximal walking speed [MWS]/6-Minute Walk Test[6MWT]), physical function (Stair Climb Test [SCT]/Timed Up and Go [TUG]), knee extension/ flexion power(KEP/KFP), joint range of motion (ROM) and pain. Standardized Mean Differences (SMD) or Mean Differences (MD) and 95% confidence intervals (CI) were calculated and combined in meta-analyses. The Cochrane Collaboration's Handbook were used for the methodological quality assessments. GRADE was used to assess the quality of evidence. The meta-analysis was performed using the RevMan 5.4 software. RESULTS: A total of 14 randomized controlled trials, involving 880 patients, were finally included. The lower-limb ARE exhibited significantly greater improvement in MWS (MD 0.13, 95%CI 0.08-0.18, P < 0.00001), TUG(MD -0.92, 95%CI -1.55- -0.28, P = 0.005), KEP (SMD 0.58, 95%CI 0.20-0.96, P = 0.003), KFP (SMD 0.38, 95%CI 0.13-0.63, P = 0.003), ROM-flexion (MD 2.74, 95%CI 1.82-3.67, P < 0.00001) and VAS (MD - 4.65, 95% CI - 7.86- -1.44, p = 0.005) compared to conventional exercise(CE) immediately post-intervention. However, there were no statistically significant differences between both groups in regard to 6MWT (MD 7.98, 95%CI -4.60-20.56, P = 0.21), SCT (MD -0.79, 95%CI -1.69-0.10, P = 0.08) and ROM-extension (MD -0.60, 95%CI -1.23-0.03, P = 0.06). CONCLUSIONS: According to the results of meta-analysis, patients undergoing TKA who receive the lower extremity ARE show better clinical effects in terms of pain relief, strength recovery and knee ROM. Simultaneously, it may be beneficial to improve mobility and physical function of patients after TKA.


Assuntos
Artroplastia do Joelho , Articulação do Joelho , Força Muscular , Osteoartrite do Joelho , Amplitude de Movimento Articular , Treinamento Resistido , Humanos , Artroplastia do Joelho/reabilitação , Artroplastia do Joelho/efeitos adversos , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Força Muscular/fisiologia , Osteoartrite do Joelho/cirurgia , Medição da Dor , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/diagnóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Treinamento Resistido/métodos , Resultado do Tratamento
8.
Plant Cell Environ ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39253954

RESUMO

Stomata are epidermal openings that facilitate plant-atmosphere gas and water exchange during photosynthesis, respiration and water evaporation. SPEECHLESS (SPCH) is a master basic helix-loop-helix (bHLH) transcription factor that determines the initiation of stomatal development. It is known that blue light promotes stomatal development through the blue light photoreceptor cryptochromes (CRYs, CRY1 and CRY2). Whether CRYs regulate stomatal development through directly modulating SPCH is unknown. Here, we demonstrate by biochemical studies that CRY1 physically interacts with SPCH in a blue light-dependent manner. Genetic studies show that SPCH acts downstream of CRY1 to promote stomatal development in blue light. Furthermore, we show that CRY1 enhances the DNA-binding activity of SPCH and promotes the expression of its target genes in blue light. These results suggest that the mechanism by which CRY1 promotes stomatal development involves positive regulation of the DNA-binding activity of SPCH, which is likely mediated by blue light-induced CRY1-SPCH interaction. The precise regulation of SPCH DNA-binding activity by CRY1 may allow plants to optimize stomatal density and pattern according to ambient light conditions.

9.
Arch Virol ; 169(9): 180, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39150572

RESUMO

Porcine epidemic diarrhea virus (PEDV) is an enteric coronavirus that has been the main cause of diarrhea in piglets since 2010 in China. The aim of this study was to investigate sequence variation and recombination events in the spike (S) gene of PEDV isolates from China. Thirty complete S gene sequences were obtained from PEDV-positive samples collected in six provinces in China from 2020 to 2023. Phylogenetic analysis showed that 10% (3/30) belonged to subtype GII-a, 6.67% (2/30) were categorized as subtype GII-b, 66.67% (20/30) were categorized as subtype GII-c, and 16.66% (5/30) were clustered with the S-INDEL strains. Amino acid sequence alignments showed that, when compared to strains of other subtypes, the GII-c strains had two characteristic amino acid substitutions (N139D and I289M). Five S-INDEL subtype strains had a single amino acid deletion (139N) and four amino acid substitutions (N118G, T137S, A138S, and D141G). Recombination analysis allowed six putative recombination events to be identified, one involving recombination between GII-c strains, two involving GII-c and GII-b strains, two involving GII-c and GI-a strains, and one involving GII-a and GI-b strains. These results suggest that recombination between PEDV strains has been common and complex in recent years and is one of the main reasons for the continuous variation of PEDV strains.


Assuntos
Infecções por Coronavirus , Vírus da Diarreia Epidêmica Suína , Recombinação Genética , Glicoproteína da Espícula de Coronavírus , Doenças dos Suínos , Animais , Sequência de Aminoácidos , Substituição de Aminoácidos , China/epidemiologia , Infecções por Coronavirus/virologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/epidemiologia , Diarreia/virologia , Diarreia/veterinária , Diarreia/epidemiologia , Variação Genética , Genótipo , Filogenia , Vírus da Diarreia Epidêmica Suína/genética , Vírus da Diarreia Epidêmica Suína/classificação , Vírus da Diarreia Epidêmica Suína/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/genética , Suínos , Doenças dos Suínos/virologia , Doenças dos Suínos/epidemiologia
10.
ACS Med Chem Lett ; 15(8): 1213-1220, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39140066

RESUMO

Developing selective CDK7 inhibitors has emerged as a promising approach for cancer treatment owing to the critical role of CDK7 in cancer progression. Starting from BTX-A51, a CK1α inhibitor that also targets CDK7 and CDK9, we designed and synthesized a series of 2,4-diaminopyrimidine derivatives as potent CDK7 inhibitors. The representative compound, 22, displayed significant enzymatic inhibitory activity and demonstrated a remarkable selectivity profile against a panel of kinases, including seven CDK subtypes. Modeling studies and molecular dynamics simulations revealed that the sulfone group of 22 significantly enhanced the binding affinity, while the acetyl group contributed to the increased selectivity of CDK7 against CDK9. Compound 22 effectively inhibited the phosphorylation of RNA polymerase II and CDK2 and resulted in G1/S phase cell cycle arrest and apoptosis in MV4-11 cells. It appears to be a promising lead compound for the development of a CDK7 inhibitor for cancer therapy.

11.
BMC Vet Res ; 20(1): 355, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39123170

RESUMO

Diarrhea is a common issue in domestic yaks (Bos grunniens) that can occur with pasture alterations and significantly impacts growth performance. Previous research has examined the microbiota of diarrhetic yaks; however, the structural changes in gut bacterial community and microbial interactions in yaks with grassland alteration-induced diarrhea remain poorly understood. To explore variations in gut microbiota homeostasis among yaks suffering from diarrhea, fecal microbiota diversity and composition were analyzed using 16 S rRNA amplicon sequencing. Gut fecal microbiota diversity was lower in diarrhetic yaks than in non-diarrhetic yaks. Furthermore, the bacterial community composition (including that of Proteobacteria and Actinobacteria) in the feces of diarrhetic yaks displayed significant alterations. Co-occurrence network analysis further underscored the compromised intestinal flora stability in yaks with diarrhea relative to that in non-diarrhetic yaks. Interestingly, the abundance of beneficial bacteria, such as Lachnospiraceae_AC2044_group and Lachnospiraceae_NK4A136_group, were decreased in yaks with diarrhea, and the reductions were negatively correlated with the fecal water content. Collectively, these findings indicate that diminished microbial stability and increased abundance of certain bacteria in the gut may contribute to diarrhea occurrence in yaks.


Assuntos
Doenças dos Bovinos , Diarreia , Fezes , Microbioma Gastrointestinal , RNA Ribossômico 16S , Animais , Bovinos , Diarreia/veterinária , Diarreia/microbiologia , Fezes/microbiologia , Doenças dos Bovinos/microbiologia , RNA Ribossômico 16S/genética , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/genética
12.
Immunobiology ; 229(5): 152791, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39180853

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrotic interstitial pneumonia with a poor prognosis and a pathogenesis that has not been fully elucidated. Oxidative stress is closely associated with IPF. In this research, we aimed to identify reliable diagnostic biomarkers associated with the oxidative stress through bioinformatics techniques. The gene expression profile data from the GSE70866 dataset was retrieved from the gene expression omnibus (GEO) database. We extracted 437 oxidative stress-related genes (ORGs) from gene set enrichment analysis (GSEA). The GSE141939 dataset was used for single-cell RNA-seq analysis to identify the expression of diagnostic genes in different cell clusters. A total of 10 differentially expressed oxidative stress-related genes (DE-ORGs) were screened. Subsequently, SOD3, CD36, ACOX2, RBM11, CYP1B1, SNCA, and MPO from the 10 DE-ORGs were identified as diagnostic genes based on random forest algorithm with randomized least absolute shrinkage and selection operator (LASSO) regression. A nomogram was constructed to evaluate the risk of disease. The decision curve analysis (DCA) and clinical impact curves indicated that the nomogram based on these seven biomarkers had extraordinary predictive power. Immune cell infiltration analysis results revealed that DE-ORGs were closely related to various immune cells, especially CYP1B1 was in positive correlation with monocytes and negative correlation with macrophages M1. Single-cell RNA-seq analysis showed that CYP1B1 was mainly associated with macrophages, and SNCA was mainly associated with basal cells. CYP1B1 and SNCA were diagnostic genes associated with oxidative stress in IPF.


Assuntos
Biomarcadores , Biologia Computacional , Fibrose Pulmonar Idiopática , Estresse Oxidativo , Humanos , Fibrose Pulmonar Idiopática/diagnóstico , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Transcriptoma , Bases de Dados Genéticas , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Prognóstico
13.
Biomimetics (Basel) ; 9(7)2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39056868

RESUMO

In this study, based on the principles of bionics, we fabricated a bionic non-smooth concave pit structure on the shoulders of friction stir welding tools and detected the thermal cycling curve, downforce, and torque of the tool in the welding process. We tested the wear loss weight and analyzed the surface morphology of the shoulder surfaces after welding for 200 m. This study found that as the distance between the concave pits decreased and the number of concave pits increased, the maximum downforce, torque, and temperature in the welding process showed a decreasing trend. As the speed increased, no matter how the tool structure changed, the downforce and torque decreased, while the peak thermal cycle temperature increased. The experimental welding results show that the wear loss weight of the non-smooth structure tool significantly reduced. The lowest wear loss weight of the tool with a concave pit interval of 1.125 mm was only 0.1529 g, which is 27% lower than that of the conventional tool. Our observations of the surface morphology of the tool shoulder after welding showed that the amount of aluminum swarf on the tool shoulder of the welding tool gradually declined with the increasing density of the uneven pits. The lowest number of aluminum chips adhered to a welding tool with a pit distance of 1.125 mm. Therefore, friction stir welding tools with biomimetic structures have better wear resistance and adhesion resistance.

14.
Materials (Basel) ; 17(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38998307

RESUMO

Geopolymers, as a novel cementitious material, exhibit typical brittle failure characteristics under stress. To mitigate this brittleness, fibers can be incorporated to enhance toughness. This study investigates the effects of varying polypropylene fiber (PPF) content and fiber length on the flowability, mechanical properties, and flexural toughness of coal gangue-based geopolymers. Microstructural changes and porosity variations within the Fiber-Reinforced Geopolymer Mortar(GMPF) matrix were observed using scanning electron microscope (SEM) and Low field NMR(LF-NMR) to elucidate the toughening mechanism of PPF-reinforced geopolymers. The introduction of fibers into the geopolymer matrix demonstrated an initial bridging effect in the viscous geopolymer slurry, with a 3.0 vol% fiber content reducing fluidity by 5.6%. Early mechanical properties of GMPF were enhanced with fiber addition; at 1.5 vol% fiber content and 15 mm length, the 3-day flexural and compressive strengths increased by 30.81% and 17.4%, respectively. Furthermore, polypropylene fibers significantly improved the matrix's flexural toughness, which showed an increasing trend with higher fiber content. At a 3.0 vol% fiber content, the flexural toughness index increased by 198.35%. The data indicated that a fiber length of 12 mm yielded the best toughening effect, with an 84.03% increase in the flexural toughness index. SEM observations revealed a strong interfacial bond between fibers and the matrix, with noticeable damage on the fiber surface due to frictional forces, and fiber pull-out being the predominant failure mode. Porosity testing results indicated that fiber incorporation substantially improved the internal pore structure of the matrix, reducing the median pore diameter of mesopores and converting mesopores to micropores. Additionally, the number of harmless and less harmful pores increased by 23.01%, while the number of more harmful pores decreased by 30.43%.

15.
J Agric Food Chem ; 72(30): 16594-16602, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38953685

RESUMO

Cigarette smoking is the acknowledged major cause of cancers of the lung and oral cavity and is an established important risk factor for multiple other cancers. DNA addition products (DNA adducts) caused by cigarette smoking are critical factors in its mechanism of carcinogenesis. However, most DNA adducts detected to date in humans cannot be specifically ascribed to smoking but rather have multiple exogenous and endogenous sources. In the study reported here, we prepared [13C]-labeled tobacco to address this problem. We report for the first time the successful growth from seeds to flowering under hydroponic conditions of highly [13C]-labeled tobacco in a controlled 13CO2 environment. The standard growth procedure with optimized conditions is described in detail. The [13C]-enrichment rate was assessed by quantifying nicotine and sugars and their [13C]-isotopologues in this tobacco using high-resolution mass spectrometry, reaching >94% in the tobacco leaves. The [13C]-labeled leaves after curing will be used to make cigarettes, allowing investigation of the specific contributions of tobacco smoke carcinogens to identified DNA adducts in smokers.


Assuntos
Isótopos de Carbono , Dano ao DNA , Hidroponia , Nicotiana , Nicotiana/química , Nicotiana/crescimento & desenvolvimento , Nicotiana/metabolismo , Isótopos de Carbono/análise , Isótopos de Carbono/metabolismo , Humanos , Adutos de DNA/metabolismo , Adutos de DNA/análise , Fumantes , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Nicotina/metabolismo
16.
Biochem Biophys Res Commun ; 724: 150233, 2024 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-38865814

RESUMO

Cryptochromes (CRYs) are blue light (BL) photoreceptors to regulate a variety of physiological processes including DNA double-strand break (DSB) repair. SUPPRESSOR OF GAMMA RADIATION 1 (SOG1) acts as the central transcription factor of DNA damage response (DDR) to induce the transcription of downstream genes, including DSB repair-related genes BRCA1 and RAD51. Whether CRYs regulate DSB repair by directly modulating SOG1 is unknown. Here, we demonstrate that CRYs physically interact with SOG1. Disruption of CRYs and SOG1 leads to increased sensitivity to DSBs and reduced DSB repair-related genes' expression under BL. Moreover, we found that CRY1 enhances SOG1's transcription activation of DSB repair-related gene BRCA1. These results suggest that the mechanism by which CRYs promote DSB repair involves positive regulation of SOG1's transcription of its target genes, which is likely mediated by CRYs-SOG1 interaction.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Criptocromos , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Criptocromos/metabolismo , Criptocromos/genética , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
17.
J Med Internet Res ; 26: e48491, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38843521

RESUMO

BACKGROUND: Social media has become an increasingly popular and critical tool for users to digest diverse information and express their perceptions and attitudes. While most studies endeavor to delineate the emotional responses of social media users, there is limited research exploring the factors associated with the emergence of emotions, particularly negative ones, during news consumption. OBJECTIVE: We aim to first depict the web coverage by news organizations on social media and then explore the crucial elements of news coverage that trigger the public's negative emotions. Our findings can act as a reference for responsible parties and news organizations in times of crisis. METHODS: We collected 23,705 Facebook posts with 1,019,317 comments from the public pages of representative news organizations in Hong Kong. We used text mining techniques, such as topic models and Bidirectional Encoder Representations from Transformers, to analyze news components and public reactions. Beyond descriptive analysis, we used regression models to shed light on how news coverage on social media is associated with the public's negative emotional responses. RESULTS: Our results suggest that occurrences of issues regarding pandemic situations, antipandemic measures, and supportive actions are likely to reduce the public's negative emotions, while comments on the posts mentioning the central government and the Government of Hong Kong reveal more negativeness. Negative and neutral media tones can alleviate the rage and interact with the subjects and issues in the news to affect users' negative emotions. Post length is found to have a curvilinear relationship with users' negative emotions. CONCLUSIONS: This study sheds light on the impacts of various components of news coverage (issues, subjects, media tone, and length) on social media on the public's negative emotions (anger, fear, and sadness). Our comprehensive analysis provides a reference framework for efficient crisis communication for similar pandemics at present or in the future. This research, although first extending the analysis between the components of news coverage and negative user emotions to the scenario of social media, echoes previous studies drawn from traditional media and its derivatives, such as web newspapers. Although the era of COVID-19 pandemic gradually brings down the curtain, the commonality of this research and previous studies also contributes to establishing a clearer territory in the field of health crises.


Assuntos
COVID-19 , Emoções , Mídias Sociais , Humanos , COVID-19/psicologia , COVID-19/epidemiologia , Hong Kong , Pandemias , Meios de Comunicação de Massa/estatística & dados numéricos , SARS-CoV-2 , Mineração de Dados/métodos
18.
Nat Mach Intell ; 6(4): 449-460, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38855263

RESUMO

The 5' UTR, a regulatory region at the beginning of an mRNA molecule, plays a crucial role in regulating the translation process and impacts the protein expression level. Language models have showcased their effectiveness in decoding the functions of protein and genome sequences. Here, we introduced a language model for 5' UTR, which we refer to as the UTR-LM. The UTR-LM is pre-trained on endogenous 5' UTRs from multiple species and is further augmented with supervised information including secondary structure and minimum free energy. We fine-tuned the UTR-LM in a variety of downstream tasks. The model outperformed the best known benchmark by up to 5% for predicting the Mean Ribosome Loading, and by up to 8% for predicting the Translation Efficiency and the mRNA Expression Level. The model also applies to identifying unannotated Internal Ribosome Entry Sites within the untranslated region and improves the AUPR from 0.37 to 0.52 compared to the best baseline. Further, we designed a library of 211 novel 5' UTRs with high predicted values of translation efficiency and evaluated them via a wet-lab assay. Experiment results confirmed that our top designs achieved a 32.5% increase in protein production level relative to well-established 5' UTR optimized for therapeutics.

19.
bioRxiv ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38853942

RESUMO

BimC family proteins are bipolar motor proteins belonging to the kinesin superfamily which promote mitosis by crosslinking and sliding apart antiparallel microtubules. Understanding the binding mechanism between the kinesin and the microtubule is crucial for researchers to make advances in the treatment of cancer and other malignancies. Experimental research has shown that the ion concentration affects the function of BimC significantly. But the insights of the ion-dependent function of BimC remain unclear. By combining molecular dynamics (MD) simulations with a series of computational approaches, we studied the electrostatic interactions at the binding interfaces of BimC and the microtubule under different KCl concentrations. We found the electrostatic interaction between BimC and microtubule is stronger at 0 mM KCl compared to 150 mM KCl, which is consistent with experimental conclusions. Furthermore, important salt bridges and residues at the binding interfaces of the complex were identified, which illustrates the details of the BimC-microtubule interactions. Molecular dynamics analyses of salt bridges identified that the important residues on the binding interface of BimC are positively charged, while those residues on the binding interface of the tubulin heterodimer are negatively charged. The finding in this work reveals some important mechanisms of kinesin-microtubule binding, which helps the future drug design for cancer therapy.

20.
Ecol Evol ; 14(6): e11570, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38898930

RESUMO

The geographical variation and domestication of tree species are an important part of the theory of forest introduction, and the tracing of the germplasm is the theoretical basis for the establishment of high-quality plantations. Chinese pine (Pinus tabuliformis Carr.) is an important native timber tree species widely distributed in northern China, but it is unclear exactly where germplasm of the main Chinese pine plantation populations originated. Here, using two mtDNA markers, we analyzed 796 individuals representing 35 populations (matR marker), and 873 individuals representing 38 populations (nad5-1 marker) of the major natural and artificial populations in northern China, respectively (Shanxi, Hebei and Liaoning provinces). The results confirmed that the core position of natural SX* populations ("*" means natural population) in the Chinese pine populations of northern China, the genetic diversity of HB and LN plantations was higher than that of natural SX* populations, and there was a large difference in genetic background within the groups of SX* and LN, HB showed the opposite. More importantly, we completed the "point by point" tracing of the HB and LN plantings. The results indicated that almost all HB populations originated from SX* (GDS*, ZTS*, GCS*, and THS*), which resulted in homogeneity of the genetic background of HB populations. Most of germplasm of the LN plantations originated from LN* (ZJS* and WF*), and the other part originated from GDS* (SX*), resulting in the large differences in the genetic background within the LN group. Our results provided a reliable theoretical basis for the scientific allocation, management, and utilization of Chinese pine populations in northern China, and for promoting the high-quality establishment of Chinese pine plantations.

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