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1.
Nature ; 629(8012): 597-602, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38658762

RESUMO

Hydroformylation is an industrial process for the production of aldehydes from alkenes1,2. Regioselective hydroformylation of propene to high-value n-butanal is particularly important, owing to a wide range of bulk applications of n-butanal in the manufacture of various necessities in human daily life3. Supported rhodium (Rh) hydroformylation catalysts, which often excel in catalyst recyclability, ease of separation and adaptability for continuous-flow processes, have been greatly exploited4. Nonetheless, they usually consist of rotationally flexible and sterically unconstrained Rh hydride dicarbonyl centres, only affording limited regioselectivity to n-butanal5-8. Here we show that proper encapsulation of Rh species comprising Rh(I)-gem-dicarbonyl centres within a MEL zeolite framework allows the breaking of the above model. The optimized catalyst exhibits more than 99% regioselectivity to n-butanal and more than 99% selectivity to aldehydes at a product formation turnover frequency (TOF) of 6,500 h-1, surpassing the performance of all heterogeneous and most homogeneous catalysts developed so far. Our comprehensive studies show that the zeolite framework can act as a scaffold to steer the reaction pathway of the intermediates confined in the space between the zeolite framework and Rh centres towards the exclusive formation of n-butanal.

2.
Nature ; 610(7933): 656-660, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36289385

RESUMO

Proposed mechanisms for the production of calcium in the first stars (population III stars)-primordial stars that formed out of the matter of the Big Bang-are at odds with observations1. Advanced nuclear burning and supernovae were thought to be the dominant source of the calcium production seen in all stars2. Here we suggest a qualitatively different path to calcium production through breakout from the 'warm' carbon-nitrogen-oxygen (CNO) cycle through a direct experimental measurement of the 19F(p, γ)20Ne breakout reaction down to a very low energy point of 186 kiloelectronvolts, reporting a key resonance at 225 kiloelectronvolts. In the domain of astrophysical interest2, at around 0.1 gigakelvin, this thermonuclear 19F(p, γ)20Ne rate is up to a factor of 7.4 larger than the previous recommended rate3. Our stellar models show a stronger breakout during stellar hydrogen burning than previously thought1,4,5, and may reveal the nature of calcium production in population III stars imprinted on the oldest known ultra-iron-poor star, SMSS0313-67086. Our experimental result was obtained in the China JinPing Underground Laboratory7, which offers an environment with an extremely low cosmic-ray-induced background8. Our rate showcases the effect that faint population III star supernovae can have on the nucleosynthesis observed in the oldest known stars and first galaxies, which are key mission targets of the James Webb Space Telescope9.

3.
Nat Mater ; 23(1): 52-57, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38052935

RESUMO

Although metallic nanostructures have been attracting tremendous research interest in nanoscience and nanotechnologies, it is known that environmental attacks, such as surface oxidation, can easily initiate cracking on the surface of metals, thus deteriorating their overall functional/structural properties1-3. In sharp contrast, here we report that severely oxidized metallic glass nanotubes can attain an ultrahigh recoverable elastic strain of up to ~14% at room temperature, which outperform bulk metallic glasses, metallic glass nanowires and many other superelastic metals hitherto reported. Through in situ experiments and atomistic simulations, we reveal that the physical mechanisms underpinning the observed superelasticity can be attributed to the formation of a percolating oxide network in metallic glass nanotubes, which not only restricts atomic-scale plastic events during loading but also leads to the recovery of elastic rigidity on unloading. Our discovery implies that oxidation in low-dimensional metallic glasses can result in unique properties for applications in nanodevices.

4.
Mol Biol Evol ; 40(9)2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37561991

RESUMO

The human brain is generally anatomically symmetrical, boasting mirror-like brain regions in the left and right hemispheres. Despite this symmetry, fine-scale structural asymmetries are prevalent and are believed to be responsible for distinct functional divisions within the brain. Prior studies propose that these asymmetric structures are predominantly primate specific or even unique to humans, suggesting that the genes contributing to the structural asymmetry of the human brain might have evolved recently. In our study, we identified approximately 1,500 traits associated with human brain asymmetry by collecting paired brain magnetic resonance imaging features from the UK Biobank. Each trait is measured in a specific region of one hemisphere and mirrored in the corresponding region of the other hemisphere. Conducting genome-wide association studies on these traits, we identified over 1,000 quantitative trait loci. Around these index single nucleotide polymorphisms, we found approximately 200 genes that are enriched in brain-related Gene Ontology terms and are predominantly upregulated in brain tissues. Interestingly, most of these genes are evolutionarily old, originating just prior to the emergence of Bilateria (bilaterally symmetrical animals) and Euteleostomi (bony vertebrates with a brain), at a significantly higher ratio than expected. Further analyses of these genes reveal a brain-specific upregulation in humans relative to other mammalian species. This suggests that the structural asymmetry of the human brain has been shaped by evolutionarily ancient genes that have assumed new functions over time.


Assuntos
Encéfalo , Estudo de Associação Genômica Ampla , Animais , Humanos , Encéfalo/diagnóstico por imagem , Vertebrados , Córtex Cerebral , Locos de Características Quantitativas , Mamíferos
5.
BMC Plant Biol ; 24(1): 1029, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39472776

RESUMO

BACKGROUND: This study clarified the synergistic relationship among annual changes to specify the changes in agro-meteorological factors, soil characteristics and peanut growth in saline-alkali land near the estuary of the Yellow River Delta. We aimed to find the key factors affecting peanut production to optimize and regulate peanut planting mode in saline alkali soil. RESULTS: The daily average temperature from early May to late September in Lijin and Kenli was above 24 °C, with 470-600 mm of precipitation. The sunshine duration was 7.9 h/day and 7.3 h/day and the accumulated temperature was 3742 °C and 3809 °C, in Lijin and Kenli, respectively. Agro-meteorological conditions were suitable for peanut growth and development with the consistent main developmental period in the two experiment regions. The best sowing period was when the soil temperature stabilized above 18 °C in early May, and the best harvest was in mid-September. The soil volumetric water content in Lijin concentrated among 25-40%. Salt was mainly distributed in the 40-60 cm soil layers, and increased rapidly to 2.5 g kg- 1 in 0-20 cm cultivation layer in mid-May due to lack of precipitation. In Kenli experiment region, the soil volumetric water content ranged from 10 to 35%. Soil salinity was mainly distributed in the 20 cm soil layer, and the changes in salinity was little affected by precipitation. From mid-July to mid-August, the effective accumulated temperature of 5 cm soil layer was above 520 °C in both regions, which could ensure the normal pod development. The slow dynamic growth of kernel, high unfilled pod rate (26.99%) and low shelling rate (66.0%) might be the main reasons for low peanut yield in Lijin. CONCLUSION: Soil salinity was the main factor affecting pod development and yield. It was also a key point in optimizing the peanut planting mode in the saline alkali land of the Yellow River Delta.


Assuntos
Arachis , Salinidade , Solo , Arachis/crescimento & desenvolvimento , Solo/química , China , Rios/química , Temperatura , Álcalis , Produção Agrícola/métodos , Estações do Ano , Estuários
6.
Small ; : e2407679, 2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39394975

RESUMO

The electrochemical C─N coupling of carbon dioxide (CO2) and nitrate(NO3 -) is an alternative strategy to the traditional high-energy industrial pathway for urea synthesis, which urgently requires the design of efficient catalysts to achieve high yield and Faraday efficiency (FE). Here, amorphous low-content copper-doped cobalt metallene boride (a-Cu0.1CoBx metallene) is designed for urea synthesis via electrochemical C─N coupling. The a-Cu0.1CoBx metallene can drive electrocatalytic C─N coupling of CO2 and NO3 - for urea synthesis in CO2-saturated 0.1 m KNO3 electrolyte, with 27.7% of FE and 312 µg h-1 mg-1 cat. of yield at -0.5 V, as well as superior cycling stability. The in situ Fourier transform infrared and theoretical calculations reveal that electronic effect between Cu, Co, and B causes Cu and Co as dual active sites to promote the adsorption of reactants. Furthermore, the introduced trace Cu reduces the reaction energy barrier of the C─N coupling to facilitate urea synthesis. This work provides a promising route for the optimization of Co-based metallene for the electrosynthesis of urea through C─N coupling.

7.
Small ; : e2403862, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39308433

RESUMO

The hydrogen peroxide (H2O2) produced through electrochemical two-electron oxygen reduction reaction (2e- ORR) is a promising green synthesis method and served as potential strategy to replace the energy-intensive anthraquinone process. Nevertheless, the design of low-cost and efficient electrocatalysts for 2e- ORR remains a formidable challenge. In this study, Sn-BiOCl nanosheets electrocatalysts are prepared for expediting the 2e- ORR, achieving a high H2O2 selectivity of 92.9%, and the H2O2 yield of 10628 mg L-1 h-1 (0.1 mg cm-2) in a flow-cell device. The in situ ATR-SEIRAS results reveal that Sn-BiOCl enhances the adsorption and activation of *OOH compared to BiOCl, resulting in higher activity and selectivity for 2e- ORR. Furthermore, this study investigates the potential for on-site production and application of H2O2 using Sn-BiOCl, which displays a 95% degradation removal of dyes (RhB, MB, and MO) within 20 min. This work not only have an insight into the critical roles of Bi and Sn atoms in enhancing the catalytic performance but also provides a thought to design efficient catalysts for production H2O2 via electrochemical 2e- ORR.

8.
Small ; : e2407446, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39422370

RESUMO

Electrochemical semi-hydrogenation of alkynols to produce high-value alkenols is a green and sustainable approach. Although Pd can exhibit excellent semi-hydrogenation properties, its intrinsic mechanism still lacks in-depth study. Herein, a proton ionic liquid (PIL)-modified Pd metallene (Pdene@PIL) is synthesized for the electrocatalytic semi-hydrogenation of 2-methyl-3-butyn-2-ol (MBY) to 2-methyl-3-buten-2-ol (MBE). The PIL modification of Pdene@PIL resulted in an MBY conversion of 96.1% and MBE selectivity of 97.2%, respectively. Theoretical calculations indicate the electron transfer between Pdene and PIL, leading to easier adsorption of MBY on the Pd surface. The d-band center of Pdene@PIL shifts away from the Fermi level, which weakens the adsorption of over-hydrogenated intermediates. At the same time, the PIL modification facilitates the adsorption of surface-adsorbed hydrogen (H*ads) and inhibits the formation of subsurface-absorbed hydrogen (H*abs). In particular, the PIL modification optimizes Hads* coverage, reduces the reaction energy of the rate-determining step (C5H8O*-C5H9O*), and inhibits HER. The reduction of H*abs formation inhibits the transfer of Pd to PdHx and suppresses the over-hydrogenation. This work provides new insights into the modulation of H* to enhance the alkynol electrocatalytic semi-hydrogenation reaction (ESHR) process from the perspective of surface modification.

9.
Small ; 20(37): e2402993, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38750614

RESUMO

2D covalent organic framework (COF) materials with extended conjugated structure and periodic columnar π-arrays exhibit promising applications in organic optoelectronics. However, there is a scarcity of reports on optoelectronic COFs, mainly due to the lack of suitable π-skeletons. Here, two multi-functional optoelectronic 2D COFs DPP-TPP-COF and DPP-TBB-COF are constructed with diketopyrrolopyrrole as electron acceptor (A), and 1,3,6,8-tetraphenylpyrene and 1,3,5-triphenylbenzene as electron donor (D) through imine bonds. Both 2D COFs showed good crystallinities and AA stacking with a rhombic framework for DPP-TPP-COF and hexagonal one for DPP-TBB-COF, respectively. The electron D-A and ordered intermolecular packing structures endow the COFs with broad UV-vis absorptions and narrow bandgaps along with suitable HOMO/LUMO energy levels, resulting in multi-functional optoelectronic properties, including photothermal conversion, supercapacitor property, and ambipolar semiconducting behavior. Among them, DPP-TPP-COF exhibits a high photothermal conversion efficiency of 47% under 660 nm laser irradiation, while DPP-TBB-COF exhibits superior specific capacitance of 384 F g-1. Moreover, P-type doping and N-type doping are achieved by iodine and tetrakis(dimethylamino)ethylene on a single host COF, resulting in ambipolar semiconducting behavior. These results provide a paradigm for the application of multi-functional optoelectronic COF materials.

10.
Small ; 20(16): e2306989, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38032164

RESUMO

Hybrid organic-inorganic perovskite (HOIP) ferroelectric materials have great potential for developing self-powered electronic transducers owing to their impressive piezoelectric performance, structural tunability and low processing temperatures. Nevertheless, their inherent brittle and low elastic moduli limit their application in electromechanical conversion. Integration of HOIP ferroelectrics and soft polymers is a promising solution. In this work, a hybrid organic-inorganic rare-earth double perovskite ferroelectric, [RM3HQ]2RbPr(NO3)6 (RM3HQ = (R)-N-methyl-3-hydroxylquinuclidinium) is presented, which possesses multiaxial nature, ferroelasticity and satisfactory piezoelectric properties, including piezoelectric charge coefficient (d33) of 102.3 pC N-1 and piezoelectric voltage coefficient (g33) of 680 × 10-3 V m N-1. The piezoelectric generators (PEG) based on composite films of [RM3HQ]2RbPr(NO3)6@polyurethane (PU) can generate an open-circuit voltage (Voc) of 30 V and short-circuit current (Isc) of 18 µA, representing one of the state-of-the-art PEGs to date. This work has promoted the exploration of new HOIP ferroelectrics and their development of applications in electromechanical conversion devices.

11.
Nat Methods ; 18(12): 1506-1514, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34857936

RESUMO

Mapping the cell phylogeny of a complex multicellular organism relies on somatic mutations accumulated from zygote to adult. Available cell barcoding methods can record about three mutations per barcode, enabling only low-resolution mapping of the cell phylogeny of complex organisms. Here we developed SMALT, a substitution mutation-aided lineage-tracing system that outperforms the available cell barcoding methods in mapping cell phylogeny. We applied SMALT to Drosophila melanogaster and obtained on average more than 20 mutations on a three-kilobase-pair barcoding sequence in early-adult cells. Using the barcoding mutations, we obtained high-quality cell phylogenetic trees, each comprising several thousand internal nodes with 84-93% median bootstrap support. The obtained cell phylogenies enabled a population genetic analysis that estimates the longitudinal dynamics of the number of actively dividing parental cells (Np) in each organ through development. The Np dynamics revealed the trajectory of cell births and provided insight into the balance of symmetric and asymmetric cell division.


Assuntos
Biologia Computacional/métodos , Drosophila melanogaster/metabolismo , Microscopia/métodos , Mutação , Alelos , Animais , Animais Geneticamente Modificados , Divisão Celular , Linhagem da Célula , Replicação do DNA , Drosophila melanogaster/embriologia , Endonucleases/metabolismo , Funções Verossimilhança , Masculino , Mutagênese , Fenótipo , Filogenia , Saccharomyces cerevisiae/genética , Análise de Célula Única
12.
Hepatology ; 78(4): 1064-1078, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36626623

RESUMO

BACKGROUND AND AIMS: HCC is a malignant disease. Compared with tyrosine kinase inhibitors (the classical therapy), immune checkpoint inhibitors are more effective in the treatment of HCC, despite their limited efficacy. Among these restricted factors, exhaustion of tumor-infiltrated lymphocytes, especially CD8 + T cells, is a core event. We aimed to determine the key factors contributing to CD8 + T-cell infiltration in HCC and investigate the underlying mechanisms. APPROACH AND RESULTS: Using machine learning and multiplex immunohistochemistry analysis, we showed that dedicator of cytokinesis protein 2 (DOCK2) was a potential indicator of infiltrated CD8 + T cells in HCC. Using RNA sequencing, flow cytometry analysis, and mouse HCC models, we demonstrated that DOCK2 inactivation accounted for infiltrated CD8 + T-cell exhaustion in tumors. Using quasi-targeted metabolomics, mass spectrum, and mass cytometry by time of flight analysis, we found that cholesterol sulfate synthesized by sulfotransferase 2B1 in tumor cells suppressed DOCK2 enzymatic activity of T cells. Through virtual screening, molecular docking simulation, and experiments validation, we demonstrated that tolazamide reversed DOCK2 inactivation-mediated CD8 + T-cell exhaustion and enhanced anti-programmed death-ligand 1 antibody+apatinib immunotherapeutic effects on HCC. CONCLUSIONS: This study indicates that DOCK2 controls CD8 + T-cell infiltration in HCC, and cholesterol sulfate synthesized by sulfotransferase 2B1 in tumor cells promotes effector T-cell exhaustion. The findings suggest that the usage of conventional drugs affects immunotherapy efficacy in HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Camundongos , Animais , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Simulação de Acoplamento Molecular , Exaustão das Células T , Linfócitos T CD8-Positivos , Sulfotransferases/metabolismo , Sulfotransferases/uso terapêutico , Microambiente Tumoral , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Fatores de Troca do Nucleotídeo Guanina/uso terapêutico , Proteínas Ativadoras de GTPase/metabolismo
13.
Opt Lett ; 49(13): 3572-3575, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950212

RESUMO

We demonstrate the post-induction of high-quality microcavities on a silicon photonic crystal (PC) waveguide by integrating a few-layer GaSe crystal, which promises efficient on-chip optical frequency conversions. The integration of GaSe shifts the dispersion bands of the PC waveguide mode into the bandgap, resulting in localized modes confined by the bare PC waveguides. Thanks to the small contrast of refractive index at the boundaries of the microcavity, it is reliable to obtain quality factors exceeding 104. With the enhanced light-GaSe interaction by the microcavity modes and GaSe's high second-order nonlinearity, remarkable second-harmonic generation (SHG) and sum-frequency generation (SFG) are achieved with continuous-wave (CW) lasers.

14.
Phys Rev Lett ; 133(11): 113203, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39331986

RESUMO

We extracted the molecular-frame elastic differential cross sections (MFDCSs) for electrons scattering from N_{2}^{+} based on elliptical laser-induced electron diffraction (ELIED), wherein the structural evolution is initialized by the same tunneling ionization and probed by incident angle-resolved laser-induced electron diffraction imaging. To establish ELIED, an intuitive interpretation of the ellipticity-dependent rescattering electron momentum distributions was first provided by analyzing the transverse momentum distribution. It was shown that the incident angle of the laser-induced returning electrons could be tuned within 20° by varying the ellipticity and handedness of the driving laser pulses. Accordingly, the incident angle-resolved DCSs of returning electrons for spherically symmetric targets (Xe^{+} and Ar^{+}) were successfully extracted as a proof-of-principle for ELIED. The MFDCSs for N_{2}^{+} were experimentally obtained at incident angles of 4° and 7°, which were well reproduced by the simulations. The ELIED approach is the only successful method so far for obtaining incident angle-resolved ionic MFDCS, which provides a new sensitive observable for the transient structure retrieval of N_{2}^{+}. Our results suggest that the ELIED has the potential to extract the structural tomographic information of polyatomic molecules with femtosecond and subangstrom spatiotemporal resolutions that can enable the visualization of the nuclear motions in complex chemical reactions as well as chiral recognition.

15.
Chemistry ; 30(27): e202400378, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38418406

RESUMO

Fluorescence imaging-guided photodynamic therapy (PDT) has attracted extensive attention due to its potential of real-time monitoring the lesion locations and visualizing the treatment process with high sensitivity and resolution. Aggregation-induced emission luminogens (AIEgens) show enhanced fluorescence and reactive oxygen species (ROS) generation after cellular uptake, giving them significant advantages in bioimaging and PDT applications. However, most AIEgens are unfavorable for the application in organisms due to their severe hydrophobicity. Anion-π+ type AIEgens carry intrinsic charges that can effectively alleviate their hydrophobicity and improve their binding capability to cells, which is expected to enhance the bioimaging quality and PDT performance. This concept summarizes the applications of anion-π+ type AIEgens in fluorescence imaging, fluorescence imaging-guided photodynamic anticancer and antimicrobial therapy in recent years, hoping to provide some new ideas for the construction of robust photosensitizers. Finally, the current problems and future challenges of anion-π+ AIEgens are discussed.


Assuntos
Ânions , Imagem Óptica , Fotoquimioterapia , Fármacos Fotossensibilizantes , Espécies Reativas de Oxigênio , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Humanos , Ânions/química , Espécies Reativas de Oxigênio/metabolismo , Corantes Fluorescentes/química , Interações Hidrofóbicas e Hidrofílicas , Neoplasias/tratamento farmacológico , Neoplasias/diagnóstico por imagem
16.
BMC Vet Res ; 20(1): 88, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459489

RESUMO

BACKGROUND: Strontium (Sr) has similar physicochemical properties as calcium (Ca) and is often used to evaluate the absorption of this mineral. Because the major route of Ca absorption in the bovine occurs in the rumen, it is essential to understand whether Sr impacts the ruminal epithelial cells and to what extent. RESULTS: In the present study, RNA sequencing and assembled transcriptome assembly were used to identify transcription factors (TFs), screening and bioinformatics analysis in bovine ruminal epithelial cells treated with Sr. A total of 1405 TFs were identified and classified into 64 families based on an alignment of conserved domains. A total of 174 differently expressed TFs (DE-TFs) were increased and 52 DE-TFs were decreased; the biological process-epithelial cell differentiation was inhibited according to the GSEA-GO analysis of TFs; The GO analysis of DE-TFs was enriched in the DNA binding. Protein-protein interaction network (PPI) found 12 hubs, including SMAD4, SMAD2, SMAD3, SP1, GATA2, NR3C1, PPARG, FOXO1, MEF2A, NCOA2, LEF1, and ETS1, which verified genes expression levels by real-time PCR. CONCLUSIONS: In this study, SMAD2, PPARG, LEF1, ETS1, GATA2, MEF2A, and NCOA2 are potential candidates that could be targeted by Sr to mediate cell proliferation and differentiation, as well as lipid metabolism. Hence, these results enhance the comprehension of Sr in the regulation of transcription factors and provide new insight into the study of Sr biological function in ruminant animals.


Assuntos
Estrôncio , Fatores de Transcrição , Humanos , Bovinos , Animais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Estrôncio/farmacologia , Estrôncio/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Perfilação da Expressão Gênica/veterinária , Células Epiteliais/metabolismo , Transcriptoma , Cálcio/metabolismo
17.
Clin Lab ; 70(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38345971

RESUMO

BACKGROUND: The aim of this study was to reveal the function of the long non-coding RNA (lncRNA) RP11-556E13.1 (RP11) and its clinical significance in hepatocellular carcinoma (HCC). METHODS: LncRNA and mRNA expression profiling was performed using lncRNA and mRNA microarrays in HCC and adjacent tissues. Human tissue samples were analyzed by semiquantitative real-time polymerase chain reaction (sqRT-PCR) to evaluate the expression of RP11. Smart silencer RNA (siRNA) was used to knockdown the expression of RP11 in HCC cells. The function of RP11 was determined by some cell function experiments in HCC cells. Western blotting (WB) was performed to detect proteins that were presumably associated with these function changes. An Affymetrix Human HTA2.0 microarray was used to detect the underlying mechanism of RP11 in HCC. RESULTS: lncRNA RP11 was the most significantly upregulated lncRNA in HCC tissues compared with the adjacent tissues (p < 0.05, fold change = 20.24). The expression of RP11 was significantly higher in HCC tissues compared to adjacent tissues in 112 tissue pairs (p < 0.05). The higher the expression of RP11 in HCC tissues, the bigger the tumor size, the poorer the histological differentiation, and the lower the overall survival rate of the patients (all p < 0.05). After the knockdown of RP11, HCC cells displayed inhibited proliferation, increased apoptosis rate, and G1/S arrest. Moreover, the expression of cleaved PARP1 and cleaved caspase-3 was increased. GO enrichment and KEGG pathway enrichment analysis showed some important pathways that might be related to the knockdown of RP11 in HCC cells. CONCLUSIONS: lncRNA RP11 is an HCC-promoting gene and a potential prognostic predictor of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Humanos , Carcinoma Hepatocelular/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Relevância Clínica , RNA Mensageiro , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral
18.
BMC Pregnancy Childbirth ; 24(1): 429, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877415

RESUMO

BACKGROUND: Postpartum depression is a complex mental health condition that often occurs after childbirth and is characterized by persistent sadness, anxiety, and fatigue. Recent research suggests a metabolic component to the disorder. This study aims to investigate the causal relationship between blood metabolites and postpartum depression using mendelian randomization (MR). METHODS: This study used a bi-directional MR framework to investigate the causal relationship between 1,400 metabolic biomarkers and postpartum depression. We used two specific genome-wide association studies datasets: one with single nucleotide polymorphisms data from mothers diagnosed with postpartum depression and another with blood metabolite data, both of which focused on people of European ancestry. Genetic variants were chosen as instrumental variables from both datasets using strict criteria to improve the robustness of the MR analysis. The combination of these datasets enabled a thorough examination of genetic influences on metabolic profiles associated with postpartum depression. Statistical analyses were conducted using techniques such as inverse variance weighting, weighted median, and model-based estimation, which enabled rigorous causal inference from the observed associations. postpartum depression was defined using endpoint definitions approved by the FinnGen study's clinical expert groups, which included leading experts in their respective medical fields. RESULTS: The MR analysis identified seven metabolites that could be linked to postpartum depression. Out of these, one metabolite was found to be protective, while six were associated with an increased risk of developing the condition. The results were consistent across multiple MR methods, indicating a significant correlation. CONCLUSIONS: This study emphasizes the potential of metabolomics for understanding postpartum depression. The discovery of specific metabolites associated with the condition sheds new insights on its pathophysiology and opens up possibilities for future research into targeted treatment strategies.


Assuntos
Depressão Pós-Parto , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Humanos , Depressão Pós-Parto/genética , Depressão Pós-Parto/sangue , Feminino , Metabolômica , Biomarcadores/sangue , Adulto , População Branca/genética , Gravidez
19.
Bull Entomol Res ; 114(2): 302-307, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38557482

RESUMO

Mosquito-borne diseases have emerged in North Borneo in Malaysia due to rapid changes in the forest landscape, and mosquito surveillance is key to understanding disease transmission. However, surveillance programmes involving sampling and taxonomic identification require well-trained personnel, are time-consuming and labour-intensive. In this study, we aim to use a deep leaning model (DL) to develop an application capable of automatically detecting mosquito vectors collected from urban and suburban areas in North Borneo, Malaysia. Specifically, a DL model called MobileNetV2 was developed using a total of 4880 images of Aedes aegypti, Aedes albopictus and Culex quinquefasciatus mosquitoes, which are widely distributed in Malaysia. More importantly, the model was deployed as an application that can be used in the field. The model was fine-tuned with hyperparameters of learning rate 0.0001, 0.0005, 0.001, 0.01 and the performance of the model was tested for accuracy, precision, recall and F1 score. Inference time was also considered during development to assess the feasibility of the model as an app in the real world. The model showed an accuracy of at least 97%, a precision of 96% and a recall of 97% on the test set. When used as an app in the field to detect mosquitoes with the elements of different background environments, the model was able to achieve an accuracy of 76% with an inference time of 47.33 ms. Our result demonstrates the practicality of computer vision and DL in the real world of vector and pest surveillance programmes. In the future, more image data and robust DL architecture can be explored to improve the prediction result.


Assuntos
Aedes , Aprendizado Profundo , Mosquitos Vetores , Animais , Malásia , Mosquitos Vetores/fisiologia , Mosquitos Vetores/classificação , Aedes/fisiologia , Aedes/classificação , Culex/classificação , Culex/fisiologia , Culicidae/classificação , Culicidae/fisiologia
20.
J Dairy Sci ; 107(8): 6340-6357, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38608939

RESUMO

Ketosis, a commonly observed energy metabolism disorder in dairy cows during the peripartal period, is distinguished by increased concentrations of BHB in the blood. This condition has a negative impact on milk production and quality, causing financial losses. An untargeted metabolomics approach was performed on plasma samples from cows between 5 and 7 DIM diagnosed as controls (CON; BHB <1.2 mM, n = 30), subclinically ketotic (SCK; 1.2 < BHB <3.0 mM, n = 30), or clinically ketotic (CK; BHB >3.0 mM, n = 30). Cows were selected from a commercial farm of 214 Holstein cows (average 305-d yield in the previous lactation of 35.42 ± 7.23 kg/d; parity, 2.41 ± 1.12; BCS, 3.1 ± 0.45). All plasma and milk samples (n = 90) were subjected to liquid chromatography-MS-based metabolomic analysis. Statistical analyses were performed using GraphPad Prism 8.0, MetaboAnalyst 4.0, and R version 4.1.3. Compared with the CON group, both SCK and CK groups had greater milk fat, freezing point, and fat-to-protein ratio, as well as lower milk protein, lactose, solids-not-fat, and milk density. Within 21 d after calving, compared with CON, the SCK group experienced a reduction of 2.65 kg/d in milk yield, while the CK group experienced a decrease of 7.7 kg/d. Untargeted metabolomics analysis facilitated the annotation of a total of 5,259 and 8,423 metabolites in plasma and milk. Differentially affected metabolites were screened in CON versus SCK, CON versus CK, and SCK versus CK (unpaired t-test, false discovery rate <0.05; and absolute value of log(2)-fold change >1.5). A total of 1,544 and 1,888 differentially affected metabolites were detected in plasma and milk. In plasma, glycerophospholipid metabolism, pyrimidine metabolism, tryptophan metabolism, sphingolipid metabolism, amino sugar and nucleotide sugar metabolism, phenylalanine metabolism, and steroid hormone biosynthesis were identified as important pathways. Weighted gene co-expression network analysis (WGCNA) indicated that tryptophan metabolism is a key pathway associated with the occurrence and development of ketosis. Increases in 5-hydroxytryptophan and decreases in kynurenine and 3-indoleacetic acid in SCK and CK were suggestive of an impact at the gut level. The decrease of most glycerophospholipids indicated that ketosis is associated with disordered lipid metabolism. For milk, pyrimidine metabolism, purine metabolism, pantothenate and CoA biosynthesis, amino sugar and nucleotide sugar metabolism, nicotinate and nicotinamide metabolism, sphingolipid metabolism, and fatty acid degradation were identified as important pathways. The WGCNA indicated that purine and pyrimidine metabolism in plasma was highly correlated with milk yield during the peripartal period. Alterations in purine and pyrimidine metabolism characterized ketosis, with lower levels of these metabolites in both milk and blood underscoring reduced efficiency in nitrogen metabolism. Our results may help to establish a foundation for future research investigating mechanisms responsible for the occurrence and development of ketosis in peripartal cows.


Assuntos
Doenças dos Bovinos , Cetose , Lactação , Metabolômica , Leite , Animais , Bovinos , Leite/química , Leite/metabolismo , Feminino , Cetose/veterinária , Cetose/metabolismo , Cetose/sangue , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/sangue
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