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1.
Hortic Res ; 11(7): uhae125, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38966867

RÉSUMÉ

Jojoba is an industrial oil crop planted in tropical arid areas, and its low-temperature sensitivity prevents its introduction into temperate areas. Studying the molecular mechanisms associated with cold acclimation in jojoba is advantageous for developing breeds with enhanced cold tolerance. In this study, metabolomic analysis revealed that various flavonols accumulate in jojoba during cold acclimation. Time-course transcriptomic analysis and weighted correlation network analysis (WGCNA) demonstrated that flavonol biosynthesis and jasmonates (JAs) signaling pathways played crucial roles in cold acclimation. Combining the biochemical and genetic analyses showed that ScMYB12 directly activated flavonol synthase gene (ScFLS). The interaction between ScMYB12 and transparent testa 8 (ScTT8) promoted the expression of ScFLS, but the negative regulator ScJAZ13 in the JA signaling pathway interacted with ScTT8 to attenuate the transcriptional activity of the ScTT8 and ScMYB12 complex, leading to the downregulation of ScFLS. Cold acclimation stimulated the production of JA in jojoba leaves, promoted the degradation of ScJAZ13, and activated the transcriptional activity of ScTT8 and ScMYB12 complexes, leading to the accumulation of flavonols. Our findings reveal the molecular mechanism of JA-mediated flavonol biosynthesis during cold acclimation in jojoba and highlight the JA pathway as a promising means for enhancing cold tolerance in breeding efforts.

2.
Anal Chem ; 2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-38975729

RÉSUMÉ

Plant samples with irregular morphology are challenging for longitudinal tissue sectioning. This has restricted the ability to gain insight into some plants using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). Herein, we develop a novel technique termed electromagnetic field-assisted frozen tissue planarization (EMFAFTP). This technique involves using a pair of adjustable electromagnets on both sides of a plant tissue. Under an optimized electromagnetic field strength, nondestructive planarization and regularization of the frozen tissue is induced, allowing the longitudinal tissue sectioning that favors subsequent molecular profiling by MALDI-MSI. As a proof of concept, flowers, leaves and roots with irregular morphology from six plant species are chosen to evaluate the performance of EMFAFTP for MALDI-MSI of secondary metabolites, amino acids, lipids, and proteins among others in the plant samples. The significantly enhanced MALDI-MSI capabilities of these endogenous molecules demonstrate the robustness of EMFAFTP and suggest it has the potential to become a standard technique for advancing MALDI-MSI into a new era of plant spatial omics.

3.
Int J Stroke ; : 17474930241266796, 2024 Jun 25.
Article de Anglais | MEDLINE | ID: mdl-38916129

RÉSUMÉ

BACKGROUND: Insulin resistance (IR) is of growing concern yet its association with white matter integrity remains controversial. We aimed to investigate the association between IR and white matter integrity in nondiabetic adults. METHODS: This cross-sectional analysis was conducted based on the PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events (PRECISE) study. A total of 1709 Nondiabetic community-dwelling adults with available diffusion weighted imaging based on brain magnetic resonance imaging and completed oral glucose tolerance test were included. IR was measured non-invasively by insulin sensitivity indices (ISI), including ISIcomposite and ISI0,120, as well as homeostasis model assessment of insulin resistance (HOMA-IR). White matter microstructure abnormalities were identified by diffusion weighted imaging along with tract-based spatial statistics analysis to compare diffusion metrics between groups. The multivariable linear regression models were applied to measure the association between white matter microstructure abnormalities and IR. RESULTS: A total of 1709 nondiabetic individuals with a mean age of 60.8±6.4 years and 53.5% female were included. We found that IR was associated with a significant increase in mean diffusivity, axial diffusivity, and radial diffusivity extensively in cerebral white matter in regions such as the anterior corona radiata, superior corona radiata, anterior limb of internal capsule, external capsule, and body of corpus callosum. The pattern of associations was more marked for ISIcomposite and ISI0,120. However, the effect of insulin resistance on white matter integrity was attenuated after additionally adjustment for history of hypertension and cardiovascular disease and antihypertensive medication use. CONCLUSION: Our findings indicate a significant association between IR and white matter microstructural abnormalities in nondiabetic middle-aged community residents, while these associations were greatly influenced by the history of hypertension and cardiovascular disease, and antihypertensive medication use. Further investigation is needed to clarify the role of IR in white matter integrity, whereas prophylactic strategies of maintaining a low IR status may ameliorate disturbances in white matter integrity.

4.
Phys Rev Lett ; 132(23): 233802, 2024 Jun 07.
Article de Anglais | MEDLINE | ID: mdl-38905673

RÉSUMÉ

Non-line-of-sight (NLOS) imaging has the ability to reconstruct hidden objects, allowing a wide range of applications. Existing NLOS systems rely on pulsed lasers and time-resolved single-photon detectors to capture the information encoded in the time of flight of scattered photons. Despite remarkable advances, the pulsed time-of-flight LIDAR approach has limited temporal resolution and struggles to detect the frequency-associated information directly. Here, we propose and demonstrate the coherent scheme-frequency-modulated continuous wave calibrated by optical frequency comb-for high-resolution NLOS imaging, velocimetry, and vibrometry. Our comb-calibrated coherent sensor presents a system temporal resolution at subpicosecond and its superior signal-to-noise ratio permits NLOS imaging of complex scenes under strong ambient light. We show the capability of NLOS localization and 3D imaging at submillimeter scale and demonstrate NLOS vibrometry sensing at an accuracy of dozen Hertz. Our approach unlocks the coherent LIDAR techniques for widespread use in imaging science and optical sensing.

6.
Front Plant Sci ; 15: 1397274, 2024.
Article de Anglais | MEDLINE | ID: mdl-38779062

RÉSUMÉ

A recombinant inbred line (RIL) population derived from wheat landrace Qingxinmai and breeding line 041133 exhibited segregation in resistance to powdery mildew and stripe rust in five and three field tests, respectively. A 16K genotyping by target sequencing (GBTS) single-nucleotide polymorphism (SNP) array-based genetic linkage map was used to dissect the quantitative trait loci (QTLs) for disease resistance. Four and seven QTLs were identified for adult-plant resistance (APR) against powdery mildew and stripe rust. QPm.caas-1B and QPm.caas-5A on chromosomes 1B and 5A were responsible for the APR against powdery mildew in line 041133. QYr.caas-1B, QYr.caas-3B, QYr.caas-4B, QYr.caas-6B.1, QYr.caas-6B.2, and QYr.caas-7B detected on the five B-genome chromosomes of line 041133 conferred its APR to stripe rust. QPm.caas-1B and QYr.caas.1B were co-localized with the pleiotropic locus Lr46/Yr29/Sr58/Pm39/Ltn2. A Kompetitive Allele Specific Polymorphic (KASP) marker KASP_1B_668028290 was developed to trace QPm/Yr.caas.1B. Four lines pyramiding six major disease resistance loci, PmQ, Yr041133, QPm/Yr.caas-1B, QPm.caas-2B.1, QYr.caas-3B, and QPm.caas-6B, were developed. They displayed effective resistance against both powdery mildew and stripe rust at the seedling and adult-plant stages.

7.
J Mech Behav Biomed Mater ; 155: 106579, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38749266

RÉSUMÉ

Silicon nitride is utilized clinically as a bioceramic for spinal fusion cages, owing to its high strength, osteoconductivity, and antibacterial effects. Nevertheless, silicon nitride exhibits suboptimal damping properties, a critical factor in mitigating traumatic bone injuries and fractures. In fact, there is a scarcity of spinal implants that simultaneously demonstrate proficient damping performance and support osteogenesis. In our study, we fabricated a novel sodium alginate-silicon nitride/poly(vinyl alcohol) (SA-SiN/PVA) composite scaffold, enabling enhanced energy absorption and rapid elastic recovery under quasi-static and impact loading scenarios. Furthermore, the study demonstrated that the incorporation of physical and chemical cross-linking significantly improved stiffness and recoverable energy dissipation. Concerning the interaction between cells and materials, our findings suggest that the addition of silicon nitride stimulated osteogenic differentiation while inhibiting Staphylococcus aureus growth. Collectively, the amalgamation of ceramics and tough hydrogels facilitates the development of advanced composites for spinal implants, manifesting superior damping, osteogenic potential, and antibacterial properties. This approach holds broader implications for applications in bone tissue engineering.


Sujet(s)
Alginates , Matériaux biocompatibles , Test de matériaux , Poly(alcool vinylique) , Composés du silicium , Staphylococcus aureus , Alginates/composition chimique , Alginates/pharmacologie , Poly(alcool vinylique)/composition chimique , Composés du silicium/composition chimique , Composés du silicium/pharmacologie , Staphylococcus aureus/effets des médicaments et des substances chimiques , Matériaux biocompatibles/composition chimique , Matériaux biocompatibles/pharmacologie , Antibactériens/pharmacologie , Antibactériens/composition chimique , Ostéogenèse/effets des médicaments et des substances chimiques , Phénomènes mécaniques , Structures d'échafaudage tissulaires/composition chimique , Humains
8.
BMC Plant Biol ; 24(1): 454, 2024 May 24.
Article de Anglais | MEDLINE | ID: mdl-38789943

RÉSUMÉ

Pleiotropy is frequently detected in agronomic traits of wheat (Triticum aestivum). A locus on chromosome 4B, QTn/Ptn/Sl/Sns/Al/Tgw/Gl/Gw.caas-4B, proved to show pleiotropic effects on tiller, spike, and grain traits using a recombinant inbred line (RIL) population of Qingxinmai × 041133. The allele from Qingxinmai increased tiller numbers, and the allele from line 041133 produced better performances of spike traits and grain traits. Another 52 QTL for the eight traits investigated were detected on 18 chromosomes, except for chromosomes 5D, 6D, and 7B. Several genes in the genomic interval of the locus on chromosome 4B were differentially expressed in crown and inflorescence samples between Qingxinmai and line 041133. The development of the KASP marker specific for the locus on chromosome 4B is useful for molecular marker-assisted selection in wheat breeding.


Sujet(s)
Allèles , Chromosomes de plante , Locus de caractère quantitatif , Triticum , Triticum/génétique , Triticum/croissance et développement , Chromosomes de plante/génétique , Phénotype , Pléiotropie , Amélioration des plantes
9.
Physiol Plant ; 176(2): e14272, 2024.
Article de Anglais | MEDLINE | ID: mdl-38566275

RÉSUMÉ

The Dehydration-Responsive Element Binding (DREB) subfamily of transcription factors plays crucial roles in plant abiotic stress response. Ammopiptanthus nanus (A. nanus) is an eremophyte exhibiting remarkable tolerance to environmental stress and DREB proteins may contribute to its tolerance to water deficit and low-temperature stress. In the present study, an A. nanus DREB A5 group transcription factor gene, AnDREB5.1, was isolated and characterized in terms of structure and function in abiotic stress tolerance. AnDREB5.1 protein is distributed in the nucleus, possesses transactivation capacity, and is capable of binding to DRE core cis-acting element. The transcription of AnDREB5.1 was induced under osmotic and cold stress. Tobacco seedlings overexpressing AnDREB5.1 displayed higher tolerance to cold stress, osmotic stress, and oxidative stress compared to wild-type tobacco (WT). Under osmotic and cold stress, overexpression of AnDREB5.1 increased antioxidant enzyme activity in tobacco leaves, inhibiting excessive elevation of ROS levels. Transcriptome sequencing analysis showed that overexpression of AnDREB5.1 raised the tolerance of transgenic tobacco seedlings to abiotic stress by regulating multiple genes, including antioxidant enzymes, transcription factors, and stress-tolerant related functional genes like NtCOR413 and NtLEA14. This study provides new evidence for understanding the potential roles of the DREB A5 subgroup members in plants.


Sujet(s)
Réponse au choc froid , Fabaceae , Réponse au choc froid/génétique , Antioxydants , Protéines végétales/métabolisme , Facteurs de transcription/métabolisme , Fabaceae/génétique , Stress physiologique/génétique , Plant/génétique , Plant/métabolisme , Nicotiana/génétique , Végétaux génétiquement modifiés/génétique , Végétaux génétiquement modifiés/métabolisme , Régulation de l'expression des gènes végétaux/génétique , Basse température
10.
Sci Bull (Beijing) ; 2024 Apr 10.
Article de Anglais | MEDLINE | ID: mdl-38664095

RÉSUMÉ

Brain aging is typically associated with a significant decline in cognitive performance. Vascular risk factors (VRF) and subsequent atherosclerosis (AS) play a major role in this process. Brain resilience reflects the brain's ability to withstand external perturbations, but the relationship of brain resilience with cognition during the aging process remains unclear. Here, we investigated how brain topological resilience (BTR) is associated with cognitive performance in the face of aging and vascular risk factors. We used data from two cross-ethnicity community cohorts, PolyvasculaR Evaluation for Cognitive Impairment and Vascular Events (PRECISE, n = 2220) and Sydney Memory and Ageing Study (MAS, n = 246). We conducted an attack simulation on brain structural networks based on k-shell decomposition and node degree centrality. BTR was defined based on changes in the size of the largest subgroup of the network during the simulation process. Subsequently, we explored the negative correlations of BTR with age, VRF, and AS, and its positive correlation with cognitive performance. Furthermore, using structural equation modeling (SEM), we constructed path models to analyze the directional dependencies among these variables, demonstrating that aging, AS, and VRF affect cognition by disrupting BTR. Our results also indicated the specificity of this metric, independent of brain volume. Overall, these findings underscore the supportive role of BTR on cognition during aging and highlight its potential application as an imaging marker for objective assessment of brain cognitive performance.

11.
Ren Fail ; 46(1): 2338929, 2024 Dec.
Article de Anglais | MEDLINE | ID: mdl-38632963

RÉSUMÉ

OBJECTIVE: To delineate the efficacy and safety profile of hemodiafiltration with endogenous reinfusion (HFR) for uremic toxin removal in patients undergoing maintenance hemodialysis (MHD). METHODS: Patients who have been on MHD for a period of at least 3 months were enrolled. Each subject underwent one HFR and one hemodiafiltration (HDF) treatment. Blood samples were collected before and after a single HFR or HDF treatment to test uremic toxin levels and to calculate clearance rate. The primary efficacy endpoint was to compare uremic toxin levels of indoxyl sulfate (IS), λ-free light chains (λFLC), and ß2-microglobulin (ß2-MG) before and after HFR treatment. Secondary efficacy endpoints was to compare the levels of urea, interleukin-6 (IL-6), P-cresol, chitinase-3-like protein 1 (YKL-40), leptin (LEP), hippuric acid (HPA), trimethylamine N-oxide (TMAO), asymmetric dimethylarginine (ADMA), tumor necrosis factor-α (TNF-α), fibroblast growth factor 23 (FGF23) before and after HFR treatment. The study also undertook a comparative analysis of uremic toxin clearance between a single HFR and HDF treatment. Meanwhile, the lever of serum albumin and branched-chain amino acids before and after a single HFR or HDF treatment were compared. In terms of safety, the study was meticulous in recording vital signs and the incidence of adverse events throughout its duration. RESULTS: The study enrolled 20 patients. After a single HFR treatment, levels of IS, λFLC, ß2-MG, IL-6, P-cresol, YKL-40, LEP, HPA, TMAO, ADMA, TNF-α, and FGF23 significantly decreased (p < 0.001 for all). The clearance rates of λFLC, ß2-MG, IL-6, LEP, and TNF-α were significantly higher in HFR compared to HDF (p values: 0.036, 0.042, 0.041, 0.019, and 0.036, respectively). Compared with pre-HFR and post-HFR treatment, levels of serum albumin, valine, and isoleucine showed no significant difference (p > 0.05), while post-HDF, levels of serum albumin significantly decreased (p = 0.000). CONCLUSION: HFR treatment effectively eliminates uremic toxins from the bloodstream of patients undergoing MHD, especially protein-bound toxins and large middle-molecule toxins. Additionally, it retains essential physiological compounds like albumin and branched-chain amino acids, underscoring its commendable safety profile.


Sujet(s)
Crésols , Hémodiafiltration , Méthylamines , Humains , Hémodiafiltration/effets indésirables , Projets pilotes , Toxines urémiques , Protéine-1 similaire à la chitinase-3 , Interleukine-6 , Facteur de nécrose tumorale alpha , Dialyse rénale , Acides aminés à chaine ramifiée , Sérumalbumine
12.
Pest Manag Sci ; 2024 Apr 27.
Article de Anglais | MEDLINE | ID: mdl-38676556

RÉSUMÉ

BACKGROUND: MicroRNAs (miRNAs) are non-coding RNAs that play a pivotal role in antiviral infection. The miR184-3p has been identified to promote rice black streaked dwarf virus (RBSDV) infection in vector Laodelphax striatellus, whether it targets other genes of L. striatellus to modulate RBSDV propagation remains unknown. RESULTS: We first analyzed the expression profiles of miR184-3p and its role in regulating RBSDV infection in L. striatellus. Then the candidate genes expression of miR184-3p were systemically analyzed with gain and loss function of miR184-3p, and the interaction of candidate gene, ecdysone inducible protein 78 (Eip78) with miR184-3p was verified by dual luciferase reporter assay. We found Eip78 is evolutionary conserved among agricultural pests and predominantly expressed in the central nervous system (CNS) of L. striatellus. Knockdown of Eip78 effectively increased RBSDV propagation and transmission. Blockade with Eip78 antibody or injection with Eip78 protein could significantly regulate RBSDV infection. Further analysis revealed that knockdown of Eip78 specifically suppresses RBSDV infection in the head part but not in the body part of L. striatellus. Besides, knockdown of ecdysone receptor (EcR) notably restricted Eip78 expression and increased RBSDV accumulation in L. striatellus. CONCLUSIONS: Taken together, we identified a novel target gene of miR184-3p, Eip78, a member of the ecdysone signaling pathway, and revealed the anti-RBSDV role of Eip78 in the CNS of L. striatellus. These results shed light on the interaction mechanisms of miRNAs, virus and ecdysone signaling pathway in insect vector. © 2024 Society of Chemical Industry.

13.
Brain Res Bull ; 211: 110939, 2024 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-38574865

RÉSUMÉ

PURPOSE: To evaluate the potential efficacy of Triptolide (TP) on cerebral ischemia/reperfusion injury (CIRI) and to uncover the underlying mechanism through which TP regulates CIRI. METHODS: We constructed a middle cerebral artery occlusion/reperfusion (MCAO/R) mouse model to simulate CIRI, and established a lipopolysaccharide (LPS)-stimulated BV-2 cell model to mimic the inflammatory state during CIRI. The neurological deficits score (NS) of mice were measured for assessment of neurologic functions. Both the severity of cerebral infarction and the apoptosis level in mouse brain tissues or cells were respectively evaluated using corresponding techniques. The expression levels of Ionized calcium binding adapter molecule 1 (IBA-1), Inductible Nitric Oxide Synthase (iNOS), Arginase 1 (Arg-1), Tumor necrosis factor-α (TNF-α), Interleukin 1ß (IL-1ß), Cysteine histoproteinase S (CTSS), Fractalkine, chemokine C-X3-C motif receptor 1 (CX3CR1), BCL-2-associated X protein (BAX), and antiapoptotic proteins (Bcl-2) were detected using immunofluorescence, qRT-PCR as well as Western blot, respectively. RESULTS: Relative to the Sham group, treatment with TP attenuated the increased NS, infarct area and apoptosis levels observed in MCAO/R mice. Upregulated expression levels of IBA-1, iNOS, Arg-1, TNF-α and IL-1ß were found in MCAO/R mice, while TP suppressed iNOS, TNF-α and IL-1ß expression, and enhanced Arg-1 expression in both MCAO/R mice and LPS-stimulated BV-2 cells. Besides, TP inhibited the CTSS/Fractalkine/CX3CR1 pathway activation in both MCAO/R mice and LPS-induced BV-2 cells, while overexpression of CTSS reversed such effect. Co-culturing HT-22 cells with TP+LPS-treated BV-2 cells led to enhanced cell viability and decreased apoptosis levels. However, overexpression of CTSS further aggravated HT-22 cell injury. CONCLUSION: TP inhibits not only microglia polarization towards the M1 phenotype by suppressing the CTSS/Fractalkine/CX3CR1 pathway activation, but also HT-22 apoptosis by crosstalk with BV-2 cells, thereby ameliorating CIRI. These findings reveal a novel mechanism of TP in improving CIRI, and offer potential implications for addressing the preventive and therapeutic strategies of CIRI.


Sujet(s)
Encéphalopathie ischémique , Diterpènes , Composés époxy , Infarctus du territoire de l'artère cérébrale moyenne , Phénanthrènes , Lésion d'ischémie-reperfusion , Transduction du signal , Animaux , Mâle , Souris , Apoptose/effets des médicaments et des substances chimiques , Encéphalopathie ischémique/traitement médicamenteux , Encéphalopathie ischémique/métabolisme , Chimiokine CX3CL1/effets des médicaments et des substances chimiques , Chimiokine CX3CL1/métabolisme , Récepteur-1 de la chimiokine CX3C/effets des médicaments et des substances chimiques , Récepteur-1 de la chimiokine CX3C/métabolisme , Modèles animaux de maladie humaine , Diterpènes/pharmacologie , Composés époxy/pharmacologie , Infarctus du territoire de l'artère cérébrale moyenne/traitement médicamenteux , Infarctus du territoire de l'artère cérébrale moyenne/métabolisme , Souris de lignée C57BL , Microglie/effets des médicaments et des substances chimiques , Microglie/métabolisme , Neuroprotecteurs/pharmacologie , Phénanthrènes/pharmacologie , Lésion d'ischémie-reperfusion/métabolisme , Lésion d'ischémie-reperfusion/traitement médicamenteux , Transduction du signal/effets des médicaments et des substances chimiques
14.
Int J Biol Macromol ; 266(Pt 1): 131020, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38521330

RÉSUMÉ

Ammopiptanthus mongolicus, a rare temperate evergreen broadleaf shrub, exhibits remarkable tolerance to low temperature and drought stress in winter. Late embryogenesis abundant (LEA) proteins, a kind of hydrophilic protein with a protective function, play significant roles in enhancing plant tolerance to abiotic stress. In this present study, we analyzed the evolution and expression of LEA genes in A. mongolicus, and investigated the function and regulatory mechanism of dehydrin under abiotic stresses. Evolutionary analysis revealed that 14 AmLEA genes underwent tandem duplication events, and 36 AmLEA genes underwent segmental duplication events Notably, an expansion in SKn-type dehydrins was observed. Expression analysis showed that AmDHN4, a SKn-type dehydrin, was up-regulated in winter and under low temperature and osmotic stresses. Functional analysis showcased that the heterologous expression of the AmDHN4 enhanced the tolerance of yeast and tobacco to low temperature stress. Additionally, the overexpression of AmDHN4 significantly improved the tolerance of transgenic Arabidopsis to low temperature, drought, and osmotic stress. Further investigations identified AmWRKY45, a downstream transcription factor in the jasmonic acid signaling pathway, binding to the AmDHN4 promoter and positively regulating its expression. In summary, these findings contribute to a deeper understanding of the functional and regulatory mechanisms of dehydrin.


Sujet(s)
Arabidopsis , Basse température , Régulation de l'expression des gènes végétaux , Pression osmotique , Protéines végétales , Arabidopsis/génétique , Arabidopsis/métabolisme , Protéines végétales/génétique , Protéines végétales/métabolisme , Végétaux génétiquement modifiés/génétique , Stress physiologique/génétique , Phylogenèse , Sécheresses , Facteurs de transcription/génétique , Facteurs de transcription/métabolisme , Saisons
15.
J Int Med Res ; 52(3): 3000605241233450, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38502002

RÉSUMÉ

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can trigger autoimmune inflammation in the liver, leading to acute autoimmune hepatitis (AIH). We herein report a case involving a 39-year-old woman with a 23-day history of yellow skin and urine. Using the revised original scoring system of the International AIH Group, we definitively diagnosed the patient with acute severe AIH (AS-AIH). She began treatment with 80 mg/day intravenous methylprednisolone, which was gradually reduced and followed by eventual transition to oral methylprednisolone. The patient finally achieved a biochemical response after 30 days of therapy, and liver transplantation was avoided. Clinicians should be aware that the onset of AS-AIH after SARS-CoV-2 infection differs from the onset of conventional AIH with respect to its clinical and pathological features. Early diagnosis and timely glucocorticoid treatment are crucial in improving outcomes.


Sujet(s)
COVID-19 , Hépatite auto-immune , Femelle , Humains , Adulte , COVID-19/complications , Hépatite auto-immune/complications , Hépatite auto-immune/diagnostic , Hépatite auto-immune/traitement médicamenteux , SARS-CoV-2 , Maladie aigüe , Méthylprednisolone/usage thérapeutique
16.
Anal Chem ; 96(13): 5160-5169, 2024 Apr 02.
Article de Anglais | MEDLINE | ID: mdl-38470972

RÉSUMÉ

Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI), which is a label-free imaging technique, determines the spatial distribution and relative abundance of versatile endogenous metabolites in tissues. Meanwhile, matrix selection is generally regarded as a pivotal step in MALDI tissue imaging. This study presents the first report of a novel MALDI matrix, 2-hydroxy-5-nitro-3-(trifluoromethyl)pyridine (HNTP), for the in situ detection and imaging of endogenous metabolites in rat liver and brain tissues by MALDI-MS in positive-ion mode. The HNTP matrix exhibits excellent characteristics, including strong ultraviolet absorption, µm-scale matrix crystals, high chemical stability, low background ion interference, and high metabolite ionization efficiency. Notably, the HNTP matrix also shows superior detection capabilities, successfully showing 185 detectable metabolites in rat liver tissue sections. This outperforms the commonly used matrices of 2,5-dihydroxybenzoic acid and 2-mercaptobenzothiazole, which detect 145 and 120 metabolites from the rat liver, respectively. Furthermore, a total of 152 metabolites are effectively detected and imaged in rat brain tissue using the HNTP matrix, and the spatial distribution of these compounds clearly shows the heterogeneity of the rat brain. The results demonstrate that HNTP is a new and powerful positive-ion mode matrix to enhance the analysis of metabolites in biological tissues by MALDI-MSI.


Sujet(s)
Imagerie diagnostique , Foie , Rats , Animaux , Spectrométrie de masse MALDI/méthodes , Foie/métabolisme , Pyridines/analyse
17.
Biochemistry ; 63(8): 958-968, 2024 Apr 16.
Article de Anglais | MEDLINE | ID: mdl-38426700

RÉSUMÉ

Bispecific antibodies (BsAbs) are undergoing continued development for applications in oncology and autoimmune diseases. While increasing activity by having more than one targeting arm, most BsAb engineering employs single Fc engagement as monoclonal antibodies. Here, we designed a novel immunoglobulin gamma-1 (IgG1)-derived dual-Fc BsAb containing two Fc regions and two distinct asymmetric antigen binding arms comprising a Fab arm and another VHH domain. In conjunction with the knob-into-hole technology, dual-Fc BsAbs could be produced with a high yield and good stability. We explore how Fc engineering effects on dual-Fc constructs could boost the desired therapeutic efficacy. This new format enabled simultaneous bispecific binding to corresponding antigens. Furthermore, compared to the one-Fc control molecules, dual-Fc BsAbs were shown to increase the avidity-based binding to FcγRs to result in higher ADCC and ADCP activities by potent avidity via binding to two antigens and Fc receptors. Overall, this novel BsAb format with enhanced effector functionalities provides a new option for antibody-based immunotherapy.


Sujet(s)
Anticorps bispécifiques , Anticorps bispécifiques/composition chimique , Fragments Fc des immunoglobulines/génétique , Anticorps monoclonaux
18.
Biomolecules ; 14(2)2024 Feb 02.
Article de Anglais | MEDLINE | ID: mdl-38397419

RÉSUMÉ

The NAC family of transcription factors (TFs) is recognized as a significant group within the plant kingdom, contributing crucially to managing growth and development processes in plants, as well as to their response and adaptation to various environmental stressors. Ammopiptanthus mongolicus, a temperate evergreen shrub renowned for its remarkable resilience to low temperatures and drought stress, presents an ideal subject for investigating the potential involvement of NAC TFs in stress response mechanisms. Here, the structure, evolution, and expression profiles of NAC family TFs were analyzed systematically, and a cold and osmotic stress-induced member, AmNAC24, was selected and functionally characterized. A total of 86 NAC genes were identified in A. mongolicus, and these were divided into 15 groups. Up to 48 and 8 NAC genes were generated by segmental duplication and tandem duplication, respectively, indicating that segmental duplication is a predominant mechanism in the expansion of the NAC gene family in A. mongolicus. A considerable amount of NAC genes, including AmNAC24, exhibited upregulation in response to cold and osmotic stress. This observation is in line with the detection of numerous cis-acting elements linked to abiotic stress response in the promoters of A. mongolicus NAC genes. Subcellular localization revealed the nuclear residence of the AmNAC24 protein, coupled with demonstrable transcriptional activation activity. AmNAC24 overexpression enhanced the tolerance of cold and osmotic stresses in Arabidopsis thaliana, possibly by maintaining ROS homeostasis. The present study provided essential data for understanding the biological functions of NAC TFs in plants.


Sujet(s)
Réponse au choc froid , Stress physiologique , Réponse au choc froid/génétique , Stress physiologique/génétique , Basse température , Facteurs de transcription/génétique , Facteurs de transcription/métabolisme , Régions promotrices (génétique) , Activation de la transcription , Régulation de l'expression des gènes végétaux , Protéines végétales/métabolisme
19.
Hum Brain Mapp ; 45(2): e26598, 2024 Feb 01.
Article de Anglais | MEDLINE | ID: mdl-38339955

RÉSUMÉ

The network nature of the brain is gradually becoming a consensus in the neuroscience field. A set of highly connected regions in the brain network called "rich-club" are crucial high efficiency communication hubs in the brain. The abnormal rich-club organization can reflect underlying abnormal brain function and metabolism, which receives increasing attention. Diabetes is one of the risk factors for neurological diseases, and most individuals with prediabetes will develop overt diabetes within their lifetime. However, the gradual impact of hyperglycemia on brain structures, including rich-club organization, remains unclear. We hypothesized that the brain follows a special disrupted pattern of rich-club organization in prediabetes and diabetes. We used cross-sectional baseline data from the population-based PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events (PRECISE) study, which included 2218 participants with a mean age of 61.3 ± 6.6 years and 54.1% females comprising 1205 prediabetes, 504 diabetes, and 509 normal control subjects. The rich-club organization and network properties of the structural networks derived from diffusion tensor imaging data were investigated using a graph theory approach. Linear mixed models were used to assess associations between rich-club organization disruptions and the subjects' glucose status. Based on the graphical analysis methods, we observed the disrupted pattern of rich-club organization was from peripheral regions mainly located in frontal areas to rich-club regions mainly located in subcortical areas from prediabetes to diabetes. The rich-club organization disruptions were associated with elevated glucose levels. These findings provided more details of the process by which hyperglycemia affects the brain, contributing to a better understanding of the potential neurological consequences. Furthermore, the disrupted pattern observed in rich-club organization may serve as a potential neuroimaging marker for early detection and monitoring of neurological disorders in individuals with prediabetes or diabetes.


Sujet(s)
Connectome , Hyperglycémie , État prédiabétique , Femelle , Humains , Adulte d'âge moyen , Sujet âgé , Mâle , Imagerie par tenseur de diffusion/méthodes , État prédiabétique/imagerie diagnostique , Études transversales , Encéphale/imagerie diagnostique , Glucose , Voies nerveuses
20.
Biomolecules ; 14(2)2024 Feb 16.
Article de Anglais | MEDLINE | ID: mdl-38397464

RÉSUMÉ

Plant cuticular wax forms a hydrophobic structure in the cuticle layer covering epidermis as the first barrier between plants and environments. Ammopiptanthus mongolicus, a leguminous desert shrub, exhibits high tolerances to multiple abiotic stress. The physiological, chemical, and transcriptomic analyses of epidermal permeability, cuticular wax metabolism and related gene expression profiles under osmotic stress in A. mongolicus leaves were performed. Physiological analyses revealed decreased leaf epidermal permeability under osmotic stress. Chemical analyses revealed saturated straight-chain alkanes as major components of leaf cuticular wax, and under osmotic stress, the contents of total wax and multiple alkane components significantly increased. Transcriptome analyses revealed the up-regulation of genes involved in biosynthesis of very-long-chain fatty acids and alkanes and wax transportation under osmotic stress. Weighted gene co-expression network analysis identified 17 modules and 6 hub genes related to wax accumulation, including 5 enzyme genes coding KCS, KCR, WAX2, FAR, and LACS, and an ABCG transporter gene. Our findings indicated that the leaf epidermal permeability of A. mongolicus decreased under osmotic stress to inhibit water loss via regulating the expression of wax-related enzyme and transporter genes, further promoting cuticular wax accumulation. This study provided new evidence for understanding the roles of cuticle lipids in abiotic stress tolerance of desert plants.


Sujet(s)
Analyse de profil d'expression de gènes , Feuilles de plante , Pression osmotique , Feuilles de plante/composition chimique , Eau/métabolisme , Alcanes , Régulation de l'expression des gènes végétaux
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