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1.
Quant Imaging Med Surg ; 14(5): 3417-3431, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38720837

RESUMO

Background: Computed tomography angiography (CTA) and digital subtraction angiography (DSA) usually raise the risk of potential malignancies with cumulative radiation doses. Current time-of-flight magnetic resonance angiography (TOF-MRA) (dubbed as cTOF), which is based on Cartesian sampling mode, may show limited diagnostic conspicuity at sinuous or branching regions. It is also prone to relatively high false positive diagnoses and undesirable display of distal intracranial vessels. This study aimed to use spiral TOF-MRA (sTOF) as a noninvasive alternative to explore possible improvement, such that the application of magnetic resonance angiography (MRA) can be extended to facilitate clinical examination or cerebrovascular disease diagnosis and follow-up studies. Methods: Initially, 37 patients with symptoms of dizziness or transient ischemic attack were consecutively recruited for suspected intracranial vascular disease examination from Zhongshan Hospital of Xiamen University between July 2020 and April 2021 in this cross-sectional prospective study. After excluding 1 patient with severe scanning artifacts, 1 patient whose scanning scope did not meet the requirement, and 1 patient with confounding tumor lesions, a total of 34 participants were included according to the inclusion and exclusion criteria. Each participant underwent intracranial vascular imaging with both sTOF and cTOF sequences on a 3.0 T MR scanner with a conventional head-neck coil of 16 channels. Contrast CTA or DSA was also performed for 15 patients showing pathology. Qualitative comparisons in terms of image quality and diagnostic efficacy ratings, quantitative comparisons in terms of signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), vessel length, and sharpness were evaluated. Pair-wise Wilcoxon test was performed to evaluate the imaging quality derived from cTOF and sTOF acquisitions and weighted Cohen's Kappa was conducted to assess the rating consistency between different physicians. Results: Compared to cTOF, sTOF showed better performance with fewer artifacts. It can effectively alleviate false positives of normal vessels being misdiagnosed as aneurysm or stenosis. Improved conspicuity was observed in cerebral distal regions with more clearly identifiable vasculature at finer scales. Quantitative comparisons in selected regions revealed significant improvement of sTOF in SNR (P<0.01 or P<0.001), CNR (P<0.001), vessel length (P<0.001), and sharpness (P<0.001) as compared to cTOF. Besides, sTOF can depict details of M1 and M2 segments of middle cerebral artery (MCA) at metallic implant region, showing its resistance to magnetic susceptibility. Conclusions: The sTOF shows higher imaging quality and lesion detectability with reduced artifacts and false positives, representing a potentially feasible surrogate in intracranial vascular imaging for future clinic routines.

3.
Magn Reson Imaging ; 111: 138-147, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38729225

RESUMO

OBJECTIVES: To explore the potential and performance of quantitative and semi-quantitative parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) based on compressed sensing volumetric interpolated breath-hold (CS-VIBE) examination in the differential diagnosis of thyroid nodules. MATERIALS AND METHODS: A total of 208 patients with 259 thyroid nodules scheduled for surgery operation were prospectively recruited. All participants underwent routine and DCE-MRI. DCE-MRI quantitative parameters [Ktrans, Kep, Ve], semi-quantitative parameters [wash-in, wash-out, time to peak (TTP), arrival time (AT), peak enhancement intensity (PEI), and initial area under curve in 60 s (iAUC)] and time-intensity curve (TIC) types were analyzed. Differential diagnostic performances were assessed using area under the receiver operating characteristic curve (AUC) and compared with the Delong test. RESULTS: Ktrans, Kep, Ve, wash-in, wash-out, PEI and iAUC were statistically significantly different between malignant and benign nodules (P < 0.001). Among these parameters, ROC analysis revealed that Ktrans showed the highest diagnostic performance in the differentiation of benign and malignant nodules, followed by wash-in. ROC analysis also revealed that Ktrans achieved the best diagnostic performance for distinguishing papillary thyroid carcinoma (PTC) from non-PTC, follicular adenoma (FA) from non-FA, nodular goiter (NG) from non-NG, with AUC values of 0.854, 0.895 and 0.609, respectively. Type III curve is frequently observed in benign thyroid nodules, accounting for 77.4% (82/106). While malignant nodules are more common in type II, accounting for 57.5% (88/153). CONCLUSION: Thyroid examination using CS-VIBE based DCE-MRI is a feasible, non-invasive method to identify benign and malignant thyroid nodules and pathological types.

4.
Small ; : e2402595, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38764288

RESUMO

The widespread adoption of aqueous Zn ion batteries is hindered by the instability of the Zn anode. Herein, an elegant strategy is proposed to enhance the stability of Zn anode by incorporating nicotinic acid (NA), an additive with a unique molecule-ion conversion mechanism, to optimize the anode/electrolyte interface and the typical ZnSO4 electrolyte system. Experimental characterization and theoretical calculations demonstrate that the NA additive preferentially replaces H2O in the original solvation shell and adsorbs onto the Zn anode surface upon conversion from molecule to ion in the electrolyte environment, thereby suppressing side reactions arising from activated H2O decomposition and stochastic growth of Zn dendrites. Simultaneously, such a molecule-to-ion conversion mechanism may induce preferential deposition of Zn along the (002) plane. Benefiting from it, the Zn||Zn symmetric battery cycles stably for 2500 h at 1 mA cm-2, 1 mAh cm-2. More encouragingly, the Zn||AC full batteries and the Zn||AC full batteries using NA electrolyte and Zn||VO2 full batteries also exhibit excellent performance improvements. This work emphasizes the role of variation in the form of additives (especially weak acid-based additives) in fine-tuning the solvation structure and the anode/electrolyte interface, hopefully enhancing the performance of various aqueous metal batteries.

5.
Front Oncol ; 14: 1241776, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774412

RESUMO

Objective: To compare image quality and diagnostic performance using different b-values for the zooming technique with diffusion-weighted imaging (ZOOMit-DWI) in thyroid nodules. Materials and methods: A total of 51 benign thyroid nodules and 50 thyroid papillary carcinomas were included. ZOOMit-DWI was performed with b-values of 0, 500, 1000, 1500 and 2000 s/mm2. The sharpness was evaluated as subjective index. The signal intensity ratio (SIR), signal-to-noise ratio (SNR) and apparent diffusion coefficient (ADC) were measured as objective indices. Pairwise comparisons were performed among the different b-value groups using the Friedman test. A receiver operating characteristic curve of the ADC value was used to evaluate diagnostic performance. The DeLong test was used to compare diagnostic effectiveness among the different b-value groups. Results: In both the papillary carcinoma group (P = 0.670) and the benign nodule group (P = 0.185), the sharpness of nodules was similar between b-values of 1000 s/mm2and 1500 s/mm2. In the papillary carcinoma group, the SIRnodule was statistically higher in DWI images with a b-value of 1500 s/mm2than in DWI images with b-values of 500 s/mm2(P = 0.004), 1000 s/mm2(P = 0.002), and 2000 s/mm2(P = 0.003). When the b-values were 1500 s/mm2(P = 0.008) and 2000 s/mm2(P = 0.009), the SIRnodule significantly differed between the papillary carcinoma group and the benign nodule group. When b = 500 s/mm2, the ADC had an AUC of 0.888. When b = 1000 s/mm2, the ADC had an AUC of 0.881. When b = 1500 s/mm2, the ADC had an AUC of 0.896. When b = 2000 s/mm2, the ADC had an AUC of 0.871. The DeLong test showed comparable diagnostic effectiveness among the different b-value groups except for between b-values of 2000 s/mm2and 1500 s/mm2, with a b-value of 2000 s/mm2showing lower effectiveness. Conclusion: This study suggests that 1500 s/mm2may be a suitable b-value to differentiate benign and malignant thyroid nodules in ZOOMit-DWI images, which yielded better image quality.

6.
Transl Vis Sci Technol ; 13(5): 8, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38739084

RESUMO

Purpose: This study aimed to evaluate the ocular characteristics associated with spontaneously high myopia in adult nonhuman primates (NHPs). Methods: A total of 537 eyes of 277 macaques with an average age of 18.53 ± 3.01 years (range = 5-26 years), raised in a controlled environment, were included. We measured ocular parameters, including spherical equivalent (SE), axial length (AXL), and intraocular pressure. The 45-degree fundus images centered on the macula and the disc assessed the fundus tessellation and parapapillary atrophy (PPA). Additionally, optical coherence tomography (OCT) was used to measure the thickness of the retinal nerve fiber layer (RNFL). Results: The mean SE was -1.58 ± 3.71 diopters (D). The mean AXL was 18.76 ± 0.86 mm. The prevalence rate of high myopia was 17.7%. As myopia aggravated, the AXL increased (r = -0.498, P < 0.001). Compared with non-high myopia, highly myopic eyes had a greater AXL (P < 0.001), less RNFL thickness (P = 0.004), a higher incidence of PPA (P < 0.001), and elevated grades of fundus tessellation (P < 0.001). The binary logistic regression was performed, which showed PPA (odds ratio [OR] = 4.924, 95% confidence interval [CI] = 2.375-10.207, P < 0.001) and higher grades of fundus tessellation (OR = 1.865, 95% CI = 1.474-2.361, P < 0.001) were independent risk characteristics for high myopia. Conclusions: In NHPs, a higher grade of fundus tessellation and PPA were significant biomarkers of high myopia. Translational Relevance: The study demonstrates adult NHPs raised in conditioned rooms have a similar prevalence and highly consistent fundus changes with human beings, which strengthens the foundation for utilizing macaques as an animal model in high myopic studies.


Assuntos
Fundo de Olho , Tomografia de Coerência Óptica , Animais , Masculino , Feminino , Modelos Animais de Doenças , Disco Óptico/patologia , Disco Óptico/diagnóstico por imagem , Atrofia Óptica/patologia , Atrofia Óptica/epidemiologia , Pressão Intraocular/fisiologia , Miopia Degenerativa/patologia , Miopia Degenerativa/epidemiologia , Fibras Nervosas/patologia , Comprimento Axial do Olho/patologia , Células Ganglionares da Retina/patologia , Miopia/patologia , Miopia/epidemiologia , Miopia/veterinária
7.
Chem Res Toxicol ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771128

RESUMO

Lung cancer is the main cause of cancer deaths around the world. Nitrosamine 4-(methyl nitrosamine)-1-(3-pyridyl)-1-butanone (NNK) is a tobacco-specific carcinogen of lung cancer. Abundant evidence implicates long noncoding RNAs (lncRNAs) in tumorigenesis. Yet, the effects and mechanisms of lncRNAs in NNK-induced carcinogenesis are still unclear. In this study, we discovered that NNK-induced transformed Beas-2B cells (Beas-2B-NNK) showed increased cell migration and proliferation while decreasing rates of apoptosis. RNA sequencing and differentially expressed lncRNAs analyses showed that lncRNA PSMB8-AS1 was obviously upregulated. Interestingly, silencing the lncRNA PSMB8-AS1 in Beas-2B-NNK cells reduced cell proliferation and migration and produced cell cycle arrest in the G2/M phase along with a decrease in CDK1 expression. Conclusively, our results demonstrate that lncRNA PSMB8-AS1 could promote the malignant characteristics of Beas-2B-NNK cells by regulating CDK1 and affecting the cell cycle, suggesting that it may supply a new prospective epigenetic mechanism for lung cancer.

8.
Clin Exp Rheumatol ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38757282

RESUMO

OBJECTIVES: To investigate whether the interplay of anti-galectin-3 antibodies (anti-Gal3 Abs) with neutrophils contributes to the development of lupus cutaneous vasculitis. METHODS: Enzyme-linked immunosorbent assay was used to determine the serum level of anti-Gal3 Abs in lupus patients. Flow cytometry, quantitative PCR and western blot were performed to investigate the expression of cell surface receptors, proinflammatory cytokines and signalling molecules in neutrophils stimulated by serum from lupus patients or healthy controls (HCs) or anti-Gal3 Ab, respectively. Immunofluorescence was performed to visualise the formation of neutrophil extracellular traps (NETs). Human umbilical vein endothelial cells were co-cultured with the supernatants from neutrophils stimulated by anti-Gal3 Ab, and cytokine production was measured at mRNA and protein levels. Immunohistochemistry was adopted to reveal the distribution of Gal3, cytokines and myeloperoxidase within lupus skin lesions. REULTS: Serum levels of anti-Gal3 Abs were negatively correlated with peripheral counts of neutrophils. Anti-Gal3 Abs positive sera from SLE patients accelerated neutrophil death, altered cell phenotype and promoted formation of NETs with the involvement of p38 MAPK pathway. Supernatants collected from neutrophils co-cultured with anti-Gal3 Ab provoked endothelial cells to produce cytokines such as IL-1, ICAM-1, SELE and particularly IL-6. Consistently, IL-6 was higher in SLE patients with anti-Gal3 Ab positive sera and enriched in the area of vascular inflammation together with enhanced expression of Gal3 protein and infiltration of neutrophils. CONCLUSIONS: Overall, these findings suggested that neutrophils were crucial mediators in anti-Gal3 Ab induced lupus cutaneous vasculitis.

9.
Bioorg Chem ; 147: 107415, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38701597

RESUMO

The tobacco mosaic virus coat protein (TMV-CP) is indispensable for the virus's replication, movement and transmission, as well as for the host plant's immune system to recognize it. It constitutes the outermost layer of the virus particle, and serves as an essential component of the virus structure. TMV-CP is essential for initiating and extending viral assembly, playing a crucial role in the self-assembly process of Tobacco Mosaic Virus (TMV). This research employed TMV-CP as a primary target for virtual screening, from which a library of 43,417 compounds was sourced and SH-05 was chosen as the lead compound. Consequently, a series of α-amide phosphate derivatives were designed and synthesized, exhibiting remarkable anti-TMV efficacy. The synthesized compounds were found to be beneficial in treating TMV, with compound 3g displaying a slightly better curative effect than Ningnanmycin (NNM) (EC50 = 304.54 µg/mL) at an EC50 of 291.9 µg/mL. Additionally, 3g exhibited comparable inactivation activity (EC50 = 63.2 µg/mL) to NNM (EC50 = 67.5 µg/mL) and similar protective activity (EC50 = 228.9 µg/mL) to NNM (EC50 = 219.7 µg/mL). Microscale thermal analysis revealed that the binding of 3g (Kd = 4.5 ± 1.9 µM) to TMV-CP showed the same level with NNM (Kd = 5.5 ± 2.6 µM). Results from transmission electron microscopy indicated that 3g could disrupt the structure of TMV virus particles. The toxicity prediction indicated that 3g was low toxicity. Molecular docking showed that 3g interacted with TMV-CP through hydrogen bond, attractive charge interaction and π-Cation interaction. This research provided a novel α-amide phosphate structure target TMV-CP, which may help the discovery of new anti-TMV agents in the future.


Assuntos
Antivirais , Proteínas do Capsídeo , Fosfatos , Vírus do Mosaico do Tabaco , Vírus do Mosaico do Tabaco/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Fosfatos/química , Fosfatos/farmacologia , Relação Estrutura-Atividade , Estrutura Molecular , Proteínas do Capsídeo/antagonistas & inibidores , Proteínas do Capsídeo/química , Proteínas do Capsídeo/metabolismo , Desenho de Fármacos , Testes de Sensibilidade Microbiana , Amidas/química , Amidas/farmacologia , Amidas/síntese química , Relação Dose-Resposta a Droga , Descoberta de Drogas , Simulação de Acoplamento Molecular
10.
Artigo em Inglês | MEDLINE | ID: mdl-38701346

RESUMO

OBJECTIVE: While some studies have suggested an association between metabolic syndrome and kidney stones, the quality and level of evidence in these studies vary. Whether some individual characteristics and clustering of metabolic syndrome traits increase the risk of kidney stones has not been examined in a large-scale prospective cohort. MATERIALS: We conducted a retrospective analysis of data from a prospective cohort of 487,860 UK Biobank participants who were free from kidney stones at baseline. The presence of metabolic syndrome was based on five criteria: abdominal obesity, high triglyceride levels, low high-density lipoprotein (HDL) cholesterol levels, high blood pressure (HBP), and type 2 diabetes mellitus (T2DM). Cox proportional hazards regression models were used to evaluate the association between metabolic syndrome and risk of kidney stones. RESULTS: After an average follow-up period of 12.6 years, a total of 5,213 of the 487,860 participants included in the UK Biobank study developed kidney stones. The partial traits of metabolic syndrome, including waist circumference (HR: 1.15, 95% CI: 1.10-1.20), HDL cholesterol (0.66, 0.55-0.79), HBP (1.11, 1.03-1.19) and T2DM (1.14, 1.04-1.21), were independently associated with the occurrence of kidney stones. The clustering of metabolic syndrome is significantly associated with kidney stone formation, and as the number of metabolic syndrome traits increases, the risk of kidney stones gradually increases. CONCLUSION: Metabolic syndrome is a significant and independent risk factor for the development of kidney stones. This association suggests that kidney stones may represent a systemic disorder influenced by the interplay of various metabolic risk factors.

12.
New Phytol ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38715078

RESUMO

Cultivated spinach (Spinacia oleracea) is a dioecious species. We report high-quality genome sequences for its two closest wild relatives, Spinacia turkestanica and Spinacia tetrandra, which are also dioecious, and are used to study the genetics of spinach domestication. Using a combination of genomic approaches, we assembled genomes of both these species and analyzed them in comparison with the previously assembled S. oleracea genome. These species diverged c. 6.3 million years ago (Ma), while cultivated spinach split from S. turkestanica 0.8 Ma. In all three species, all six chromosomes include very large gene-poor, repeat-rich regions, which, in S. oleracea, are pericentromeric regions with very low recombination rates in both male and female genetic maps. We describe population genomic evidence that the similar regions in the wild species also recombine rarely. We characterized 282 structural variants (SVs) that have been selected during domestication. These regions include genes associated with leaf margin type and flowering time. We also describe evidence that the downy mildew resistance loci of cultivated spinach are derived from introgression from both wild spinach species. Collectively, this study reveals the genome architecture of spinach assemblies and highlights the importance of SVs during the domestication of cultivated spinach.

13.
14.
Small ; : e2309907, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38712486

RESUMO

The biophysical properties of the extracellular matrix (ECM) play a pivotal role in modulating cancer progression via cell-ECM interactions. However, the biophysical properties specific to gastric cancer (GC) remain largely unexplored. Pertinently, GC ECM shows significantly heterogeneous metamorphoses, such as matrix stiffening and intricate restructuring. By combining collagen I and alginate, this study designs an in vitro biomimetic hydrogel platform to independently modulate matrix stiffness and structure across a physiological stiffness spectrum while preserving consistent collagen concentration and fiber topography. With this platform, this study assesses the impacts of matrix biophysical properties on cell proliferation, migration, invasion, and other pivotal dynamics of AGS. The findings spotlight a compelling interplay between matrix stiffness and structure, influencing both cellular responses and ECM remodeling. Furthermore, this investigation into the integrin/actin-collagen interplay reinforces the central role of integrins in mediating cell-ECM interactions, reciprocally sculpting cell conduct, and ECM adaptation. Collectively, this study reveals a previously unidentified role of ECM biophysical properties in GC malignant potential and provides insight into the bidirectional mechanical cell-ECM interactions, which may facilitate the development of novel therapeutic horizons.

15.
Hortic Res ; 11(4): uhae054, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38706581

RESUMO

Lily bulbils, which serve as advantageous axillary organs for vegetative propagation, have not been extensively studied in terms of the mechanism of bulbil initiation. The functions of auxin and sucrose metabolism have been implicated in axillary organ development, but their relationship in regulating bulbil initiation remains unclear. In this study, exogenous indole-3-acetic acid (IAA) treatment increased the endogenous auxin levels at leaf axils and significantly decreased bulbil number, whereas treatment with the auxin polar transport inhibitor N-1-naphthylphthalamic acid (NPA), which resulted in a low auxin concentration at leaf axils, stimulated bulbil initiation and increased bulbil number. A low level of auxin caused by NPA spraying or silencing of auxin biosynthesis genes YUCCA FLAVIN MONOOXYGENASE-LIKE 6 (LlYUC6) and TRYPTOPHAN AMINOTRANSFERASERELATED 1 (LlTAR1) facilitated sucrose metabolism by activating the expression of SUCROSE SYNTHASES 1 (LlSusy1) and CELL WALL INVERTASE 2 (LlCWIN2), resulting in enhanced bulbil initiation. Silencing LlSusy1 or LlCWIN2 hindered bulbil initiation. Moreover, the transcription factor BASIC HELIX-LOOP-HELIX 35 (LlbHLH35) directly bound the promoter of LlSusy1, but not the promoter of LlCWIN2, and activated its transcription in response to the auxin content, bridging the gap between auxin and sucrose metabolism. In conclusion, our results reveal that an LlbHLH35-LlSusy1 module mediates auxin-regulated sucrose metabolism during bulbil initiation.

16.
Heliyon ; 10(9): e29925, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38707306

RESUMO

Background: Radiotherapy is an effective treatment for hepatocellular carcinoma (HCC). Recent studies indicated that N7-methylguanosine (m7G)-associated genes are involved in radioresistance and prognosis of HCC. However, the prognostic value and underlying mechanism of m7G-and radiosensitivity-associated genes are still lacking. Methods: The related statistics of HCC were downloaded from The Cancer Genome Atlas (TCGA). M7G- and radiosensitivity-associated genes were screened and evaluated using correlation, differential, univariate, and multivariate analysis. The least absolute shrinkage and selection operator (LASSO) algorithm was used to establish a prognostic model. Prognostic efficacy, functional analysis, immune cell infiltration,and drug sensitivity of the prognostic model were assessed. The ceRNA network was predicted and evaluated through the StarBase database, correlation analysis, expression analysis, and survival analysis. Result: METTL1, EIF3D, NCBP2, and WDR4 participated in prognosis model construction. The favorable prediction efficiency has been verified in both the training and verification sets. Different risk groups have differences in prognosis outcome, function analysis, immune cell infiltration, and drug sensitivity. NCBP2 can be used to predict the prognosis and has excellent potential in immunotherapy. A prognostic ceRNA network based on the NCBP2/miR-122-5p axis was established. Conclusion: The prognosis model of m7G- and radiosensitivity-related genes is constructed, and widely used in clinical prognosis, immunotherapy, and drug therapy. NCBP2, as a hub gene, may be a prognostic biomarker for HCC and is related to immunotherapy. Establishing the NCBP2/miR-122-5p axis helps study the mechanism of ceRNA and provides new ideas for finding a new candidate biomarker.

17.
Chembiochem ; : e202400285, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752893

RESUMO

ω-Transaminases (ω-TAs) are attractive biocatalysts asymmetrically catalyzing ketones to chiral amines. However, poor non-native catalytic activity and substrate promiscuity severely hamper its wide application in industrial production. Protein engineering efforts have generally focused on reshaping the substrate-binding pockets of ω-TAs. However, hotspots around the substrate tunnel as well as distant sites outside the pockets may also affect its activity. In this study, the ω-TA from Bacillus megaterium (BmeTA) was selected for engineering. The tunnel mutation Y164F synergy with distant mutation A245T which was acquired through a multiple sequence alignment showed improved soluble expression, a 3.7-fold higher specific activity and a 19.9-fold longer half-life at 45℃. Molecule Dynamics simulation explains the mechanism of improved catalytic activity, enhanced thermostability and improved soluble expression of BmeTAY164F/A245T(2M). Finally, the resting cells of 2M were used for biocatalytic processes. 450 mM of S-methoxyisopropylamine (S-MOIPA) was obtained with an ee value of 97.3% and a conversion rate of 90%, laying the foundation for its industrial production. Mutant 2M was also found to be more advantageous in catalyzing the transamination of various ketones. These results demonstrated that sites that are far away from the active center also play an important role in the redesign of ω-TAs.

18.
J Am Chem Soc ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38742912

RESUMO

Composite oxides have been widely applied in the hydrogenation of CO/CO2 to methanol or as the component of bifunctional oxide-zeolite for the synthesis of hydrocarbon chemicals. However, it is still challenging to disentangle the stepwise formation mechanism of CH3OH at working conditions and selectively convert CO2 to hydrocarbon chemicals with narrow distribution. Here, we investigate the reaction network of the hydrogenation of CO2 to methanol over a series of spinel oxides (AB2O4), among which the Zn-based nanostructures offer superior performance in methanol synthesis. Through a series of (quasi) in situ spectroscopic characterizations, we evidence that the dissociation of H2 tends to follow a heterolytic pathway and that hydrogenation ability can be regulated by the combination of Zn with Ga or Al. The coordinatively unsaturated metal sites over ZnAl2Ox and ZnGa2Ox originating from oxygen vacancies (OVs) are evidenced to be responsible for the dissociative adsorption and activation of CO2. The evolution of the reaction intermediates, including both carbonaceous and hydrogen species at high temperatures and pressures over the spinel oxides, has been experimentally elaborated at the atomic level. With the integration of a series of zeolites or zeotypes, high selectivities of hydrocarbon chemicals with narrow distributions can be directly produced from CO2 and H2, offering a promising route for CO2 utilization.

19.
Opt Lett ; 49(9): 2469-2472, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691746

RESUMO

This Letter presents a real-time coherent receiver using digital signal processing (DSP)-assisted automatic frequency control (AFC) to compensate for the Doppler frequency shift (DFS). DFS compensation range of ±8 GHz and the frequency shifting rate of 33 MHz/s are demonstrated in an FPGA-based 2.5 Gbaud QPSK coherent optical system. The experimental results indicate that the scheme achieves a sensitivity of -47 dBm at a bit error rate (BER) of 2E-4. The power penalty induced by the DFS compensation is less than 1 dB.

20.
Virology ; 595: 110093, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38692134

RESUMO

Oncolytic virotherapy stands out as a burgeoning and promising therapeutic paradigm, harnessing the intrinsic cytotoxicity of oncolytic viruses for selective replication and dissemination within tumors. The primary mode of action revolves around the direct eradication of tumor cells. In our previous investigations, we formulated an oncolytic herpes simplex virus type 2 (OH2) and substantiated its anti-tumor efficacy both in vivo and in vitro. Subsequently, we embarked on a phase I/II clinical trial in China (NMPA, 2018L02743) and the USA (FDA, IND 27137) to assess OH2's safety, biodistribution, and anti-tumor activity as a standalone agent in patients with advanced solid tumors. In this investigation, our primary focus was to comprehend the influence of the major capsid protein VP5 of OH2 on its efficacy as an antitumor agent. Our findings underscore that the VP5 protein significantly amplifies OH2's oncolytic impact on A549 cells. Additionally, we observed that VP5 actively promotes the induction of apoptosis in A549 cells, both in vivo and in vitro. Through comprehensive transcriptional sequencing, we further authenticated that the VP5 protein triggers apoptosis-related signaling pathways and Gene Ontology (GO) terms in A549 cells. Moreover, we scrutinized differentially expressed genes in the p53-dependent apoptosis pathway and conducted meticulous in vitro validation of these genes. Subsequently, we delved deeper into unraveling the functional significance of the TP53I3 gene and conclusively affirmed that the VP5 protein induces apoptosis in A549 cells through the TP53I3 gene. These revelations illuminate the underlying mechanisms of OH2's antitumor activity and underscore the pivotal role played by the VP5 protein. The outcomes of our study harbor promising implications for the formulation of effective oncolytic virotherapy strategies in cancer treatment.


Assuntos
Apoptose , Herpesvirus Humano 2 , Terapia Viral Oncolítica , Vírus Oncolíticos , Humanos , Vírus Oncolíticos/genética , Vírus Oncolíticos/fisiologia , Células A549 , Terapia Viral Oncolítica/métodos , Animais , Herpesvirus Humano 2/fisiologia , Herpesvirus Humano 2/genética , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
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