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1.
J Am Chem Soc ; 146(28): 18948-18957, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38959409

RESUMO

Single-molecule localization methods have been popularly exploited to obtain super-resolved images of biological structures. However, the low blinking frequency of randomly switching emission states of individual fluorophores greatly limits the imaging speed of single-molecule localization microscopy (SMLM). Here we present an ultrafast SMLM technique exploiting spontaneous fluorescence blinking of cyanine dye aggregates confined to DNA framework nanostructures. The DNA template guides the formation of static excimer aggregates as a "light-harvesting nanoantenna", whereas intermolecular excitation energy transfer (EET) between static excimers causes collective ultrafast fluorescence blinking of fluorophore aggregates. This DNA framework-based strategy enables the imaging of DNA nanostructures with 12.5-fold improvement in speed compared to conventional SMLM. Further, we demonstrate the use of this strategy to track the movement of super-resolved DNA nanostructures for over 20 min in a microfluidic system. Thus, this ultrafast SMLM holds great potential for revealing the dynamic processes of biomacromolecules in living cells.


Assuntos
DNA , Corantes Fluorescentes , Nanoestruturas , DNA/química , Corantes Fluorescentes/química , Nanoestruturas/química , Imagem Individual de Molécula/métodos , Carbocianinas/química , Microscopia de Fluorescência/métodos
2.
Materials (Basel) ; 17(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38998312

RESUMO

The production of aluminum alloy multi-lumen tubes primarily involves hot bending formation, a process where controlling thermal deformation quality is difficult. Specifically, the inner cavity wall of the tube is prone to bending instability defects under the bending stress field. To address these challenges in the bending deformation of aluminum alloy multi-lumen tubes, a multi-lumen liquid-filled bypass forming method is proposed in this paper. This study focuses on the 6063-T5 aluminum alloy double-lumen tube as the research object. The liquid-filled bending deformation behavior of the aluminum alloy double-lumen tube was investigated, and the deformation theory of the aluminum alloy double-lumen tube was studied. Through experimental and numerical simulation methods, the influence of support internal pressure, bending radius, and tube wall thickness on the liquid-filled bending deformation behavior of the double-lumen tube was examined. The results indicate that when the value of internal pressure was 7.5 MPa, the straightening of the outer wall was improved by 2.51%, the thinning rate of wall thickness was minimized, and the internal concave defect was effectively suppressed. The liquid-filled bending method provides a promising new approach for the integrated bending and forming of multi-lumen tubes.

4.
Int J Biol Macromol ; 276(Pt 2): 133987, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39032875

RESUMO

This paper aims to investigate the current situation of cancer related fibroblasts promoting malignant development of cancer through FOXO1 protein/LIF signal, and explore the strategy of cancer treatment. Recent studies have shown that the expression of the protein forkhead box O1 (FOXO1) is increased in CAFsCAFs (Cancer-associated fibroblasts). This led researchers to investigate whether FOXO1 is involved in the role of CAFs in lung cancer. The results of the study revealed that FOXO1 is indeed upregulated in CAFs, and it positively regulates the transcription of another protein called LIF. Notably, LIF is also upregulated in both CAFs and lung cancer cells. These changes in protein expression were associated with the overexpression of FOXO1 in CAFs. Conversely, silencing FOXO1 in CAFs suppressed their effects on cancer cells and transplanted tumors. The study revealed that the downregulation of LIFR in cancer cells abolished the impact of CAFs overexpressing FOXO1 on cancer cell behavior. This suggests that the FOXO1/LIF signaling pathway is involved in mediating the malignant development of lung cancer induced by CAFs.

5.
Front Plant Sci ; 15: 1400213, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39040505

RESUMO

Cinnamyl alcohol dehydrogenase (CAD) plays a crucial role in lignin biosynthesis, and the gene family encoding various CAD isozymes has been cloned and characterized in numerous plant species. However, limited information regarding the CAD gene family in tobacco is currently available. In this study, we identified 10 CAD genes in Nicotiana tabacum, four in N. tomentosiformis, and six in N. sylvestris. The nucleotide and amino acid sequences of these tobacco CADs demonstrate high levels of similarity, whereas the putative protein sequences conservatively possessed two Zn2+ binding motifs and an NADP(H) cofactor binding motif. Both NtCAD1 and NtCAD2 had conservative substrate binding sites, similar to those possessed by bona fide CADs, and evidence from phylogenetic analysis as well as expression profiling supported their role as bona fide CADs involved in lignin biosynthesis. NtCAD1 has two paralogous genes, NtCAD1-1 and NtCAD1-2. Enzyme activity analysis revealed that NtCAD1-1 and NtCAD1-2 had a high affinity to coniferyl aldehyde, p-coumaryl aldehyde, and sinapyl aldehyde, whereas NtCAD2 preferred coniferyl aldehyde and p-coumaryl aldehyde as substrates. The kinetic parameter assay revealed that NtCAD1-2 functions as the most efficient enzyme. Downregulation of both NtCAD1-1 and NtCAD1-2 resulted in reddish-brown stems without significant changes in lignin content. Furthermore, NtCAD1-1, NtCAD1-2, and NtCAD2 showed distinct expression patterns in response to biotic and abiotic stresses, as well as different phytohormones. Our findings suggest that NtCAD1-1 and NtCAD1-2 are involved in lignin biosynthesis, with NtCAD1-2 also participating in both biological and abiotic stresses, whereas NtCAD2 plays a distinct role mainly in responding to biological and abiotic stresses in tobacco.

7.
Int Immunopharmacol ; 139: 112701, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39024747

RESUMO

Current evidence suggests that porcine circovirus type 2 (PCV2) infection induces immunosuppression in piglets. Sophora subprostrate polysaccharide (SSP) exhibits various pharmacological activities, including immunoregulatory, anti-inflammatory, antiviral, and antioxidant properties. However, the acts of lncRNAs in regulating the therapeutic effects of SSP on PCV2-infected RAW264.7 cells remains poorly understood. This study aimed to investigate the molecular mechanisms by which lncRNAs regulate PCV2-induced immunosuppression during SSP treatment. Our findings revealed that 1699 mRNAs, 373 lncRNAs, and 129 miRNAs were differentially expressed in PCV2-infected RAW264.7 cells. Additionally, 359 mRNAs, 271 lncRNAs, and 79 miRNAs exhibited differential expression in SSP-treated PCV2-infected RAW264.7 cells. GO and KEGG analyses indicated that the candidate genes were enriched in the TNF/NF-κB signaling pathway. Furthermore, based on GO and KEGG pathway analysis, a ceRNA network involving chemokine (C-X-C motif) ligand 2 (CXCL2), miR-217-x, and MSTRG.5823.1 was constructed. We demonstrated that lncRNA MSTRG.5823.1 localized to the cytoplasm. Moreover, we found that silencing or overexpressing lncRNA MSTRG.5823.1 significantly modulated PCV2-induced immunosuppression by regulating the activation of the TNF/NF-κB signaling pathway. Specifically, lncRNA MSTRG.5823.1 overexpression increased the expression of TNF/NF-κB signaling pathway-related genes and proteins in PCV2-infected RAW264.7 cells. Conversely, silencing lncRNA MSTRG.5823.1 decreased their expression. Rescue assays further revealed that the suppressive effects of miR-217-x overexpression on TNF/NF-κB signaling pathway-related genes and proteins could be reversed by MSTRG.5823.1 overexpression. These findings highlight the critical role of lncRNA MSTRG.5823.1 in PCV2 infection progression and suggest a new strategy for the prevention and treatment of PCV2 infection.

8.
J Neurosurg ; : 1-8, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38875716

RESUMO

OBJECTIVE: Previous randomized controlled trials have reported a significantly higher occlusion rate of large and giant aneurysms when utilizing the Tubridge flow diverter (FD). In the present trial, the safety and efficacy of the Tubridge FD in treating unruptured internal carotid artery (ICA) or vertebral artery (VA) aneurysms were assessed in a real-world setting. METHODS: The Intracranial Aneurysms Managed by Parent Artery Reconstruction Using Tubridge Flow Diverter (IMPACT) study is a prospective, multicenter, single-arm clinical trial assessing the efficacy of the Tubridge FD in the management of unruptured aneurysms located in the ICA or VA. The primary endpoint was the complete occlusion (Raymond-Roy class 1) rate at the 1-year follow-up. The secondary endpoints included the technical success rate, the successful occlusion rate of the aneurysm, which is the degree of aneurysm embolization scored as Raymond-Roy class 1 or 2, major (> 50%) in-stent stenosis, and incidence of disabling stroke or neurological death associated with the target aneurysms. RESULTS: This study included 14 interventional neuroradiology centers, with 200 patients and 240 aneurysms. According to angiographic core laboratory assessment, 205 (85.4%) aneurysms were located in the ICA, 34 (14.2%) in the VA, and 1 (0.4%) in the middle cerebral artery. Additionally, 189 (78.8%) aneurysms were small (< 10 mm). At the 12-month follow-up, the total occlusion rate was 79.0% (166/210, 95% CI 72.91%-84.34%). Additionally, the occurrence of disabling stroke or neurological death related to the specified aneurysms was 1% (2/200). CONCLUSIONS: The 1-year results from the IMPACT trial affirm the safety record of use of the Tubridge FD in the treatment of intracranial aneurysms in real-world scenarios. These results reveal low morbidity and mortality rates of 3.5% and 1.5%, respectively. Furthermore, they provide evidence of the effectiveness of the Tubridge FD, as demonstrated by the complete occlusion achieved in 166 of 210 (79%) cases.

9.
Sci Total Environ ; 945: 173856, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38871315

RESUMO

Regional transport plays a crucial role in the pollution of fine particulate matter (PM2.5) over the Yangtze River Delta region (YRD). A practical joint regional emission control strategy requires quantitative assessment of the contribution of regional transport. In this study, the contribution of inter-city transport to PM2.5 among the 41 cities in the YRD region were quantitatively estimated using a source-oriented chemical transport model, and then the relationship between the cumulative contribution of regional transport and the distance was examined using the Michaelis-Menten equation. The results show that the Michaelis-Menten equation is suitable to represent the relationship between the cumulative contribution and transport distance. The coefficient of determination (r2) of the fittings is greater than 0.9 in 71 % of the cases in the six subregions and four seasons in YRD. Two key parameters in the Michaelis-Menten eq. K1, indicating the maximum contribution of regional transport, and K2, indicating the distance to which the regional transport contribution reach half the maximum contribution, show substantial regional and seasonal variations. The average K1 is 73.6 %, with lower values observed in the northern part of the YRD and higher values in central Jiangsu. K2 is larger in northern Jiangsu, as well as central and southern Zhejiang. The local contribution in autumn and winter is lower than that in spring and summer in the northern part of the YRD. Particularly in northern Jiangsu, the local contribution reaches 90.4 % in summer but drops to 53.0 % in autumn and winter, illustrating significant impacts of regional transport to PM2.5 in autumn and winter in this area. K2 is larger on polluted days, compared to clean days, indicating greater contributions from regional transport to PM2.5 in YRD. The results can serve as a scientific foundation for implementing regional joint prevention and control measures in the YRD region.

10.
Mater Today Bio ; 26: 101067, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38706730

RESUMO

The blood-brain Barrier (BBB), combined with immune clearance, contributes to the low efficacy of drug delivery and suboptimal treatment outcomes in glioma. Here, we propose a novel approach that combines the self-assembly of mouse bone marrow-derived macrophage membrane with a targeted positive charge polymer (An-PEI), along with low-frequency ultrasound (LFU) irradiation, to achieve efficient and safe therapy for glioma. Our findings demonstrate the efficacy of a charge-induced self-assembly strategy, resulting in a stable co-delivery nanosystem with a high drug loading efficiency of 44.2 %. Moreover, this structure triggers a significant release of temozolomide in the acidic environment of the tumor microenvironment. Additionally, the macrophage membrane coating expresses Spyproteins, which increase the amount of An-BMP-TMZ that can evade the immune system by 40 %, while LFU irradiation treatment facilitates the opening of the BBB, allowing for enormously increased entry of An-BMP-TMZ (approximately 400 %) into the brain. Furthermore, after crossing the BBB, the Angiopep-2 peptide-modified An-BMP-TMZ exhibits the ability to selectively target glioma cells. These advantages result in an obvious tumor inhibition effect in animal experiments and significantly improve the survival of glioma-bearing mice. These results suggest that combining the macrophage membrane-coated drug delivery system with LFU irradiation offers a feasible approach for the accurate, efficient and safe treatment of brain disease.

11.
World J Gastrointest Oncol ; 16(5): 1849-1860, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38764830

RESUMO

BACKGROUND: Lymph node (LN) staging in rectal cancer (RC) affects treatment decisions and patient prognosis. For radiologists, the traditional preoperative assessment of LN metastasis (LNM) using magnetic resonance imaging (MRI) poses a challenge. AIM: To explore the value of a nomogram model that combines Conventional MRI and radiomics features from the LNs of RC in assessing the preoperative metastasis of evaluable LNs. METHODS: In this retrospective study, 270 LNs (158 nonmetastatic, 112 metastatic) were randomly split into training (n = 189) and validation sets (n = 81). LNs were classified based on pathology-MRI matching. Conventional MRI features [size, shape, margin, T2-weighted imaging (T2WI) appearance, and CE-T1-weighted imaging (T1WI) enhancement] were evaluated. Three radiomics models used 3D features from T1WI and T2WI images. Additionally, a nomogram model combining conventional MRI and radiomics features was developed. The model used univariate analysis and multivariable logistic regression. Evaluation employed the receiver operating characteristic curve, with DeLong test for comparing diagnostic performance. Nomogram performance was assessed using calibration and decision curve analysis. RESULTS: The nomogram model outperformed conventional MRI and single radiomics models in evaluating LNM. In the training set, the nomogram model achieved an area under the curve (AUC) of 0.92, which was significantly higher than the AUCs of 0.82 (P < 0.001) and 0.89 (P < 0.001) of the conventional MRI and radiomics models, respectively. In the validation set, the nomogram model achieved an AUC of 0.91, significantly surpassing 0.80 (P < 0.001) and 0.86 (P < 0.001), respectively. CONCLUSION: The nomogram model showed the best performance in predicting metastasis of evaluable LNs.

12.
Environ Sci Technol ; 58(20): 8685-8695, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38709795

RESUMO

Forecasting alterations in ambient air pollution and the consequent health implications is crucial for safeguarding public health, advancing environmental sustainability, informing economic decision making, and promoting appropriate policy and regulatory action. However, predicting such changes poses a substantial challenge, requiring accurate data, sophisticated modeling methodologies, and a meticulous evaluation of multiple drivers. In this study, we calculate premature deaths due to ambient fine particulate matter (PM2.5) exposure in India from the 2020s (2016-2020) to the 2100s (2095-2100) under four different socioeconomic and climate scenarios (SSPs) based on four CMIP6 models. PM2.5 concentrations decreased in all SSP scenarios except for SSP3-7.0, with the lowest concentration observed in SSP1-2.6. The results indicate an upward trend in the five-year average number of deaths across all scenarios, ranging from 1.01 million in the 2020s to 4.12-5.44 million in the 2100s. Further analysis revealed that the benefits of reducing PM2.5 concentrations under all scenarios are largely mitigated by population aging and growth. These findings underscore the importance of proactive measures and an integrated approach in India to improve atmospheric quality and reduce vulnerability to aging under changing climate conditions.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Material Particulado , Índia , Humanos , Poluentes Atmosféricos/análise , Exposição Ambiental , Clima
13.
Int J Oncol ; 65(1)2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38785142

RESUMO

Following the publication of the above article, a concerned reader drew to the Editor's attention that certain of the Transwell invasion assay data shown in Fig. 5B on p. 911 were strikingly similar to data that had appeared in a previously published paper written by different authors at a different research institute. In view of the fact that certain of the data in the above article had already appeared in a previously published paper, the Editor of International Journal of Oncology has decided that this paper should be retracted from the publication. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused. [International Journal of Oncology 54: 905­915, 2019; DOI: 10.3892/ijo.2018.4637].

14.
Talanta ; 276: 126270, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38761662

RESUMO

Liquid biopsies utilizing tumor exosomes offer a noninvasive approach for cancer diagnosis. However, validation studies consistently report that in the early stages of cancer, the secretion of exosomes by cancer cells is relatively low, while bodily fluids exhibit a high abundance of other interfering biomolecules. Additionally, target mutations or differences in biomarker expression among various lung cancer subtypes may contribute to detection failures. In this study, we propose a targeted nanoarray-based early cancer diagnostic approach for multiple subtypes of lung cancer. The targeted nanoarray was constructed by modifying five targeting aptamers onto mesoporous silica nanoparticles through the conjugation between amino and carboxyl groups. The flow cytometry experiments demonstrated the specific recognition ability of the targeted nanoarray to tumor exosomes in PBS, even at biomarker expression levels as low as 1.5 %. Moreover, the TEM results indicated that the targeted nanoarray could isolate tumor exosomes in the blood of tumor-bearing mice. Furthermore, the targeted nanoarray could detect tumor exosomes in the blood of various lung cancer bearing mice, including at the early stages of cancer, which has just been established for 7 days. Overall, the targeted nanoarray represents a promising tool for the early detection of various subtypes of lung cancer.


Assuntos
Exossomos , Neoplasias Pulmonares , Dióxido de Silício , Exossomos/química , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico , Animais , Humanos , Camundongos , Dióxido de Silício/química , Nanopartículas/química , Detecção Precoce de Câncer/métodos , Biomarcadores Tumorais/sangue , Aptâmeros de Nucleotídeos/química , Biópsia Líquida/métodos , Camundongos Nus , Camundongos Endogâmicos BALB C , Linhagem Celular Tumoral
15.
Gene ; 922: 148458, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38608796

RESUMO

AIMS: To investigate the association between single nucleotide polymorphisms (SNPs) in 3'UTR region of VAX1, SYT14 and PAX7 genes and the risk of non-syndromic cleft palate (NSCLP) in a northwest Chinese population. MAIN METHODS: A case-control study was conducted in 406 normal controls and 399 NSCLP patients. Using iMLDRTM genotyping technology, eight SNPs of three genes ((rs10787760, rs7086344 at VAX1), (rs1010113, rs851114, and rs485874 at PAX7), and (rs61820397, rs4609425, rs12133399 at SYT14)) were genotyped to investigate the differences in alleles and genotype distribution frequencies between NSCLP patients and healthy controls. RNA Folding Form software was used to predict RNA secondary structure and expression vectors were constructed to explore the function of the relevant SNP. The effect of SNP polymorphism of gene transcription and translation was assessed using qPCR and Western blot analysis. KEY FINDINGS: Among the eight SNPs of three genes, rs10787760 of VAX1 gene was found to be associated with an increased risk of NSCLP (OR = 1.341, CI = 1.004-1.790) and the GA genotype of rs10787760 increased the risk of cleft lip and/or palate (CL/P) about 1.42 times (p < 0.05), and carrying the A allele might increase the risk of NSCL/P in male (OR = 1.356, 95 % CI = 1.010-1.823). But there was no association observed with cleft palate only (CPO). Cell function experiments revealed that the G to A mutation in rs10787760 up-regulated GFP-VAX1 transcriptional level by 2.39 and 3.13 times in two cell lines respectively, and enhance the protein expression of the VAX1 gene further. RNA secondary structure study showed that the rs10787760 (G > A) had two different secondary structures in 3'UTR region. SIGNIFICANCE: The rs10787760 variant in the 3'UTR region of VAX1 gene is associated with CL/P in northwest Chinese population. We hypothesize that the machanism of it might be caused by the RNA differenct fold in the 3'UTR region caused by the polymorphism of the gene. LEVEL OF EVIDENCE: Original Reports.


Assuntos
Regiões 3' não Traduzidas , Povo Asiático , Fissura Palatina , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Humanos , Masculino , Regiões 3' não Traduzidas/genética , Feminino , Fissura Palatina/genética , Estudos de Casos e Controles , China , Povo Asiático/genética , Regulação para Cima/genética , Genótipo , População do Leste Asiático
16.
Genetics ; 227(2)2024 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-38560786

RESUMO

An attractive perfume is a complex mixture of compounds, some of which may be unpleasant on their own. This is also true for the volatile combinations from yeast fermentation products in vineyards and orchards when assessed by Drosophila. Here, we used crosses between a yeast strain with an attractive fermentation profile and another strain with a repulsive one and tested fly responses using a T-maze. QTL analysis reveals allelic variation in four yeast genes, namely PTC6, SAT4, YFL040W, and ARI1, that modulated expression levels of volatile compounds [assessed by gas chromatography-mass spectrometry (GC-MS)] and in different combinations, generated various levels of attractiveness. The parent strain that is more attractive to Drosophila has repulsive alleles at two of the loci, while the least attractive parent has attractive alleles. Behavioral assays using artificial mixtures mimicking the composition of odors from fermentation validated the results of GC-MS and QTL mapping, thereby directly connecting genetic variation in yeast to attractiveness in flies. This study can be used as a basis for dissecting the combination of olfactory receptors that mediate the attractiveness/repulsion of flies to yeast volatiles and may also serve as a model for testing the attractiveness of pest species such as Drosophila suzukii to their host fruit.


Assuntos
Drosophila , Locos de Características Quantitativas , Animais , Drosophila/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Alelos , Masculino , Feminino , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Comportamento Animal , Compostos Orgânicos Voláteis/metabolismo , Odorantes/análise
17.
Sci Adv ; 10(15): eadk4027, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608020

RESUMO

Drought is a major global challenge in agriculture that decreases crop production. γ-Aminobutyric acid (GABA) interfaces with drought stress in plants; however, a mechanistic understanding of the interaction between GABA accumulation and drought response remains to be established. Here we showed the potassium/proton exchanger TaNHX2 functions as a positive regulator in drought resistance in wheat by mediating cross-talk between the stomatal aperture and GABA accumulation. TaNHX2 interacted with glutamate decarboxylase TaGAD1, a key enzyme that synthesizes GABA from glutamate. Furthermore, TaNHX2 targeted the C-terminal auto-inhibitory domain of TaGAD1, enhanced its activity, and promoted GABA accumulation under drought stress. Consistent with this, the tanhx2 and tagad1 mutants showed reduced drought tolerance, and transgenic wheat with enhanced TaNHX2 expression had a yield advantage under water deficit without growth penalty. These results shed light on the plant stomatal movement mechanism under drought stress and the TaNHX2-TaGAD1 module may be harnessed for amelioration of negative environmental effects in wheat as well as other crops.


Assuntos
Resistência à Seca , Triticum , Triticum/genética , Ácido Glutâmico , Proteínas de Membrana Transportadoras , Potássio , Ácido gama-Aminobutírico
18.
Drug Metab Dispos ; 52(5): 432-441, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38485279

RESUMO

Drug-induced liver injury (DILI) is a frequent cause of clinical trial failures during drug development. While inhibiting bile salt export pump (BSEP) is a well-documented DILI mechanism, interference with genes related to bile acid (BA) metabolism and transport can further complicate DILI development. Here, the effects of twenty-eight compounds on genes associated with BA metabolism and transport were evaluated, including those with discontinued development or use, boxed warnings, and clean labels for DILI. The study also included rifampicin and omeprazole, pregnane X receptor and aryl hydrocarbon receptor ligands, and four mitogen-activated protein kinase kinase (MEK1/2) inhibitors. BSEP inhibitors with more severe DILI, notably pazopanib and CP-724714, significantly upregulated the expression of 7 alpha-hydroxylase (CYP7A1), independent of small heterodimer partner (SHP) expression. CYP7A1 expression was marginally induced by omeprazole. In contrast, its expression was suppressed by mometasone (10-fold), vinblastine (18-fold), hexachlorophene (2-fold), bosentan (2.1-fold), and rifampin (2-fold). All four MEK1/2 inhibitors that show clinical DILI were not potent BSEP inhibitors but significantly induced CYP7A1 expression, accompanied by a significant SHP gene suppression. Sulfotransferase 2A1 and BSEP were marginally upregulated, but no other genes were altered by the drugs tested. Protein levels of CYP7A1 were increased with the treatment of CYP7A1 inducers and decreased with obeticholic acid, an farnesoid X receptor ligand. CYP7A1 inducers significantly increased bile acid (BA) production in hepatocytes, indicating the overall regulatory effects of BA metabolism. This study demonstrates that CYP7A1 induction via various mechanisms can pose a risk for DILI, independently or in synergy with BSEP inhibition, and it should be evaluated early in drug discovery. SIGNIFICANCE STATEMENT: Kinase inhibitors, pazopanib and CP-724714, inhibit BSEP and induce CYP7A1 expression independent of small heterodimer partner (SHP) expression, leading to increased bile acid (BA) production and demonstrating clinically elevated drug-induced liver toxicity. MEK1/2 inhibitors that show BSEP-independent drug-induced liver injury (DILI) induced the CYP7A1 gene accompanied by SHP suppression. CYP7A1 induction via SHP-dependent or independent mechanisms can pose a risk for DILI, independently or in synergy with BSEP inhibition. Monitoring BA production in hepatocytes can reliably detect the total effects of BA-related gene regulation for de-risking.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Indazóis , Pirimidinas , Sulfonamidas , Humanos , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Doença Hepática Induzida por Substâncias e Drogas/genética , Omeprazol/efeitos adversos , Ácidos e Sais Biliares , Colesterol 7-alfa-Hidroxilase/metabolismo
19.
Proc Natl Acad Sci U S A ; 121(11): e2312596121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38437555

RESUMO

Self-assembled DNA crystals offer a precise chemical platform at the ångström-scale for DNA nanotechnology, holding enormous potential in material separation, catalysis, and DNA data storage. However, accurately controlling the crystallization kinetics of such DNA crystals remains challenging. Herein, we found that atomic-level 5-methylcytosine (5mC) modification can regulate the crystallization kinetics of DNA crystal by tuning the hybridization rates of DNA motifs. We discovered that by manipulating the axial and combination of 5mC modification on the sticky ends of DNA tensegrity triangle motifs, we can obtain a series of DNA crystals with controllable morphological features. Through DNA-PAINT and FRET-labeled DNA strand displacement experiments, we elucidate that atomic-level 5mC modification enhances the affinity constant of DNA hybridization at both the single-molecule and macroscopic scales. This enhancement can be harnessed for kinetic-driven control of the preferential growth direction of DNA crystals. The 5mC modification strategy can overcome the limitations of DNA sequence design imposed by limited nucleobase numbers in various DNA hybridization reactions. This strategy provides a new avenue for the manipulation of DNA crystal structure, valuable for the advancement of DNA and biomacromolecular crystallography.


Assuntos
5-Metilcitosina , DNA , Cristalização , Catálise , Cristalografia
20.
Sci Total Environ ; 923: 171353, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38432390

RESUMO

Black carbon (BC) exerts a profound and intricate impact on both air quality and climate due to its high light absorption. However, the uncertainty in representing the absorption enhancement of BC in climate models leads to an increased range in the modeled aerosol climate effects. Changes in BC optical properties could result either from atmospheric aging processes or from variations in its sources. In this study, a source-age model for identifying emission sources and aging states presented by University of California at Davis/California Institute of Technology (UCD/CIT) was used to simulate the atmospheric age distribution of BC from different sources and to quantify its impact on the optical properties of BC-containing particles. The results indicate that regions with greater aged BC concentrations do not correspond to regions with higher BC emissions due to atmospheric transport. High concentrations of aged BC are found in northern Yangtze River Delta (YRD) regions during summer. The chemical compositions of particles from different sources and with different atmospheric ages differ significantly. BC and primary organic aerosols (POA) are dominating in Traffic-dominated source while other components dominate in Industry-dominated source. As the atmospheric age increases, the mass fraction of secondary inorganic aerosols rises. Compared to the original model, the simulated mass absorption cross section of BC particles in the source-age model decreases while the single scattering albedo increases. This compensates for ~11 % of the overestimation of the simulated BC direct radiative forcing. Our study highlights that incorporating atmospheric age and source information into models can greatly improve the estimation of optical properties of BC-containing particles and deepen our understanding of their climate effects.

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