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1.
Analyst ; 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38847183

ABSTRACT

Benefitting from the rapid evolution of artificial intelligence and structural biology, an expanding collection of high-resolution protein structures has greatly improved our understanding of protein functions. Yet, proteins are inherently flexible, and these static structures can only offer limited snapshots of their true dynamic nature. The conformational and functional changes of calmodulin (CaM) induced by Ca2+ binding have always been a focus of research. In this study, the conformational dynamics of CaM and its complexes were investigated using a mobility capillary electrophoresis (MCE) and native mass spectrometry (native MS) based method. By analyzing the ellipsoidal geometries of CaM in the solution phase at different Ca2+ concentrations, it is interesting to discover that CaM molecules, whether bound to Ca2+ or not, possess both closed and open conformations. Moreover, each individual CaM molecule actively "jumps" (equilibrium exchange) between these two distinct conformations on a timescale ranging from milli- to micro-seconds. The binding of Ca2+ ions did not affect the structural dynamics of CaM, while the binding of a peptide ligand would stabilize CaM, leading to the observation of a single, compact conformation of the resulting protein complex. A target recognition mechanism was also proposed based on these new findings, suggesting that CaM's interaction with targets may favor a conformational selection model. This enriches our understanding of the binding principles between CaM and its numerous targets.

2.
Chem Sci ; 15(23): 8993-8999, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38873081

ABSTRACT

Aromatization-driven deconstruction and functionalization of spiro dihydroquinazolinones via dual photoredox/nickel catalysis is developed. The aromatization effect was introduced to synergistically drive unstrained cyclic C-C bond cleavage, with the aim of overcoming the ring-size limitation of nitrogen-centered radical induced deconstruction of carbocycles. Herein, we demonstrate the synergistic photoredox/nickel catalyzed deconstructive cross-coupling of spiro dihydroquinazolinones with organic halides. Remarkably, structurally diverse organic halides including aryl, alkenyl, alkynyl, and alkyl bromides were compatible for the coupling. In addition, this protocol is also characterized by its mild and redox-neutral conditions, excellent functional group compatibility, high atom economy, and easy scalability. A telescoped procedure involving condensation and ring-opening/coupling was found to be accessible. This work provides a complementary strategy to the existing radical-mediated C-C bond cleavage of unstrained carbocycles.

3.
Phytochemistry ; 225: 114171, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38844058

ABSTRACT

Seven undescribed abietane diterpenoids [abietamethinols A-G (1-7)] were isolated from the twigs and leaves of Isodon amethystoides. Their structures were elucidated on the basis of spectroscopic methods including 2D NMR, and they were further confirmed by X-ray crystallographic data. Lophanic acid was considered as the precursor of 1-7 in the biosynthesis pathway hypothesis. These compounds were evaluated for their cytotoxic, anti-bacterial and anti-AIV (avian influenza virus) activities. Compound 5 showed 42.9% inhibitory activity against the cancer cell line SMMC-7721 at the concentration of 40 µM, 3 and 4 could inhibit the bacterial growth of Streptococcus sobrinus by 55.3% and 63.2% at the concentrations of 148.6 and 141.9 µM, respectively, and 4 was demonstrated with antiviral activity against AIV with the inhibitory effect of 68.4% at 25 µM.

4.
Cell ; 187(13): 3231-3232, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38906099

ABSTRACT

Numerous studies have evaluated the gut microbiome as a biomarker for predicting cancer immunotherapy, but the heterogeneity among different studies has hindered its applications. In this issue of Cell, Derosa et al. report a biomarker based on the ecological topology of the gut microbiota that can predict immunotherapy efficacy effectively.


Subject(s)
Gastrointestinal Microbiome , Immunotherapy , Neoplasms , Gastrointestinal Microbiome/immunology , Humans , Immunotherapy/methods , Neoplasms/therapy , Neoplasms/immunology , Biomarkers/metabolism , Biomarkers, Tumor/metabolism
5.
BMC Public Health ; 24(1): 1669, 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38909187

ABSTRACT

BACKGROUND: With rapid urbanization, massive migration, and non-family-based eldercare involvement, Chinese concepts of eldercare responsibility and filial piety are shifting. We performed age-period-cohort (APC) analyses to assess the transition of old-age pension coverage, eldercare responsibility, and filial piety concepts and its urban-rural differences among Chinese adults using data from the China General Social Survey (2006-2017). METHODS: Old-age pension coverage (yes/no) and primary eldercare responsibility (government/offspring/self/sharing) were investigated in 2010, 2012, 2013, 2015, and 2017. Filial piety was evaluated using customized questionnaires in 2006 and 2017. The APC effects were estimated using mixed effects and generalized additive models. RESULTS: Among 66,182 eligible participants (mean age: 48.8 years, females: 51.7%) in the six waves, APC analyses indicated that old-age pension coverage increased with aging and over time. Across cohort groups, it grew as the cohort was younger in urban residents but decreased in rural residents. The concept of offspring-based (> 50%) and government/self/offspring-shared eldercare (> 30%) predominated. APC analyses revealed that the offspring-based concept declined with aging (OR = 0.81, 95% CI: 0.79-0.84), whereas the government-based (OR = 1.37, 95% CI: 1.33-1.41) and self-based (OR = 1.55, 95% CI: 1.47-1.63) concepts increased with aging. People born around the 1940s have a comparatively higher possibility to perceive that the primary eldercare responsibility should be undertaken by the government and elder parents. In contrast, people born in the younger cohort were more likely to perceive that adult children are responsible for their parents' primary eldercare. Filial piety score slightly increased with aging (ß = 0.18, SD: 0.05) but decreased as the birth cohort was younger. In addition, rural participants were more likely to perceive offspring-based eldercare and maintain filial piety, and the related urban-rural difference was intensified by aging. CONCLUSIONS: The traditional concept that eldercare solely relies on offspring has changed to relying on multiple entities, including the government and self-reliance. Diluted filial piety in people born in the young cohort requires reinforcement. Moreover, future healthy aging policies need to focus more on urban-rural disparities to promote equity in social well-being.


Subject(s)
Rural Population , Urban Population , Humans , China , Female , Male , Middle Aged , Rural Population/statistics & numerical data , Aged , Urban Population/statistics & numerical data , Adult , Cohort Studies , Intergenerational Relations , Pensions/statistics & numerical data , Surveys and Questionnaires , Social Responsibility
6.
Acta Pharm Sin B ; 14(6): 2748-2760, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38828155

ABSTRACT

Circular RNAs (circRNAs) are ideal biomarkers of oral squamous cell carcinoma (OSCC) because of their highly stable closed-loop structure, and they can act as microRNA (miRNA) sponges to regulate OSCC progression. By analyzing clinical samples, we identified circCPNE1, a dysregulated circRNA in OSCC, and its expression level was negatively correlated with the clinical stage of OSCC patients. Gain-of-function assays revealed the tumor-suppressive effect of circCPNE1, which was then identified as a miR-330-3p sponge. MiR-330-3p was recognized as a tumor promoter in multiple studies, consistent with our finding that it could promote the proliferation, migration, and invasion of OSCC cells. These results indicated that selective inhibition of miR-330-3p could be an effective strategy to inhibit OSCC progression. Therefore, we designed cationic polylysine-cisplatin prodrugs to deliver antagomiR-330-3p (a miRNA inhibitory analog) via electrostatic interactions to form PP@miR nanoparticles (NPs). Paratumoral administration results revealed that PP@miR NPs effectively inhibited subcutaneous tumor progression and achieved partial tumor elimination (2/5), which confirmed the critical role of miR-330-3p in OSCC development. These findings provide a new perspective for the development of OSCC treatments.

7.
Int Ophthalmol ; 44(1): 249, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38907177

ABSTRACT

OBJECTIVE: To investigate the macular morphological and visual outcomes of combined idiopathic epiretinal membrane (iERM) removal with triamcinolone acetonide (TA) injection based on consideration of the ectopic inner foveal layer (EIFL) staging scheme. METHODS: Retrospective case-control study. The clinical data of 84 eyes of 84 patients who underwent vitrectomy for iERM between 2018 and 2022 were reviewed. The enrolled subjects were divided into the TA and non-TA groups. Fifty-one eyes received intravitreal TA injection following vitrectomy and ERM peeling (TA group), and 33 were only treated by standard vitrectomy and ERM peeling (non-TA group). Preoperative and postoperative EIFL stages, central foveal thickness (CFT), and best-corrected visual acuity (BCVA) were compared between both groups. RESULTS: After a mean follow-up of 7.69 ± 3.68 months, both groups exhibited significant improvement in EIFL stages (P < 0.01), with no discernible advantage observed in the TA group. The TA and non-TA groups demonstrated improvement in the EIFL stages in 56.86 and 63.64% of eyes, respectively (P = 0.43). The CFT and BCVA significantly improved in both groups at the final visit (P < 0.01). However, CFT in the non-TA group displayed a more significant reduction during the follow-up (P < 0.03). Subgroup analysis revealed no significant differences in postoperative CFT and BCVA between the two groups in cases with or without continuous EIFL (P > 0.10). CONCLUSION: Our findings indicate that combined intravitreal TA injection following ERM removal conferred no significant benefits in alleviating macular thickening or improving visual acuity in iERM.


Subject(s)
Epiretinal Membrane , Fovea Centralis , Glucocorticoids , Intravitreal Injections , Tomography, Optical Coherence , Triamcinolone Acetonide , Visual Acuity , Vitrectomy , Humans , Epiretinal Membrane/diagnosis , Epiretinal Membrane/surgery , Retrospective Studies , Male , Female , Tomography, Optical Coherence/methods , Glucocorticoids/administration & dosage , Fovea Centralis/pathology , Vitrectomy/methods , Triamcinolone Acetonide/administration & dosage , Case-Control Studies , Aged , Middle Aged , Follow-Up Studies , Treatment Outcome
8.
Cell Host Microbe ; 32(6): 783-785, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38870895

ABSTRACT

Previous studies have explored the role of the gut microbiota in regulating endobiotic homeostasis, but the precise mechanisms remain unclear. In this issue of Cell Host & Microbe, Simpson et al. identified two predominant subtypes of gut microbial ß-Glucuronidase (gmGUS) that can reactivate hormones and neurotransmitters to regulate endobiotic homeostasis.


Subject(s)
Gastrointestinal Microbiome , Glucuronidase , Homeostasis , Glucuronidase/metabolism , Glucuronidase/genetics , Gastrointestinal Microbiome/physiology , Humans , Animals , Gastrointestinal Tract/microbiology , Bacteria/enzymology , Bacteria/metabolism , Bacteria/genetics
9.
J Affect Disord ; 359: 308-318, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38795780

ABSTRACT

BACKGROUND: Generalized anxiety disorder (GAD) is the least successfully treated anxiety disorder. This clinical trial investigated the effects and efficacy of a novel self-compassion intervention in GAD. METHODS: A total of 75 GAD patients were assigned to a self-compassion intervention group (n = 25), a mindfulness intervention group (n = 25), or a treat-as-usual group (n = 25). Patients in the two active groups received eight intervention sessions in two weeks in addition to usual treatment i.e., pharmacotherapy. Primary outcomes were anxiety and worry, assessed at pre-intervention, post-intervention, and three-month follow-up. Secondary outcomes included depression, sleep, as well as self-compassion and mindfulness. RESULTS: Both the self-compassion and mindfulness intervention induced a more rapid decrease in anxiety and depression than pharmacological treatment alone with excellent response and remission rate. Self-compassion intervention also induced a more rapid improvement in sleep quality compared to mindfulness intervention and pharmacological treatment alone. We also presented a mechanism for the self-compassion intervention in which decreased anxiety led to improvement in sleep quality. There was also a higher pleasure, acceptance, and willingness to re-attend in the self-compassion compared to the mindfulness intervention. LIMITATIONS: This study was single blinded and nonrandomized which may bring risks of bias. CONCLUSIONS: Overall, we provided novel evidence that self-compassion intervention is an alternative psychotherapy for GAD with excellent response and acceptability.


Subject(s)
Anxiety Disorders , Empathy , Mindfulness , Humans , Female , Anxiety Disorders/therapy , Male , Adult , Mindfulness/methods , Middle Aged , Treatment Outcome , Depression/therapy , Self Concept , Sleep Quality
10.
Zhongguo Zhong Yao Za Zhi ; 49(10): 2783-2797, 2024 May.
Article in Chinese | MEDLINE | ID: mdl-38812179

ABSTRACT

Dihuang Baoyuan Granules is a prescription endorsed by HU Tianbao, a renowned and elderly Chinese medicine practitioner from Beijing, and has demonstrated definite clinical efficacy. The composition of this prescription is intricate as it includes 7 distinct herbal medicines. This study aims to analyze the chemical composition of Dihuang Baoyuan Granules, evaluate its efficacy in the treatment of diabetes and analyze the distribution of the drug components in the plasma, liver, and kidney after administration. The findings will serve as a reference for future research on pharmacodynamic substances of this prescription. UHPLC-LTQ-Orbitrap MS was employed to analyze the main chemical components of Dihuang Baoyuan Granules. A Waters ACQUITY Premier HSS T3 column(2.1 mm×100 mm, 1.8 µm) was used for chromatographic separation with 0.1% formic acid(A)-acetonitrile(B) as the mobile phases in a gradient elution at a flow rate of 0.3 mL·min~(-1). Electrospray ionization(ESI) source was used to acquire data in positive and negative ion modes. Furthermore, a rat model of diabetes mellitus was established by feeding with a high-sugar high-fat diet, and injection with streptozocin at a dose of 35 mg·kg~(-1), and the modeled rats were then administrated with Dihuang Baoyuan Granules. The fasting blood glucose, hemoglobin A1c, and other relevant indicators were measured, and the substances present in the plasma, liver, and kidney were identified. By reference to quasi-molecular ions, MS/MS fragment ions, MS spectra of reference substances, and compound information in available reports, 191 components were identified in Dihuang Baoyuan Granules, including 29 alkaloids, 24 flavonoids, 22 organic acids, 16 amino acids, 12 terpenes, 11 steroid saponins, 9 sugars, 8 phenylethanoid glycosides, 8 nucleosides, 2 phenylpropanoids, and 49 others compounds. Eighty-three chemical components were identified in rat plasma, 109 in the liver, and 98 in the kidney. Component identification and characterization of Dihuang Baoyuan Granules in vitro and in vivo provide efficacy information and guidance for the basic research on the pharmacodynamic substances and further clinical application of this prescription.


Subject(s)
Drugs, Chinese Herbal , Rats, Sprague-Dawley , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacokinetics , Chromatography, High Pressure Liquid/methods , Animals , Rats , Male , Humans , Liver/drug effects , Liver/chemistry , Liver/metabolism , Mass Spectrometry/methods , Kidney/drug effects , Kidney/chemistry , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus/drug therapy
12.
Diagnostics (Basel) ; 14(10)2024 May 16.
Article in English | MEDLINE | ID: mdl-38786328

ABSTRACT

While high-dose therapy and autologous stem cell transplant (ASCT) remain integral to the primary treatment of newly diagnosed transplant-elble multiple myeloma (MM) patients, the challenge of disease progression persists. The primary objective of this meta-analysis is to evaluate the efficacy and safety of tandem ASCT compared to single ASCT. We conducted a systematic review and meta-analysis of randomized controlled trials and observational studies comparing tandem ASCT with single ASCT in patients with newly diagnosed MM. We searched PubMed, EMBASE, Cochrane Library, and Clinical Trials databases for studies published up to January 2024. The primary outcomes were progression-free survival (PFS), overall survival (OS), overall response rate (ORR), complete response rate (CRR), and treatment-related mortality (TRM). We used a random-effects model to calculate pooled hazard ratios (HRs) and relative risks (RRs) with 95% confidence intervals (CIs). Study quality was assessed using the Cochrane risk of bias tool and Newcastle-Ottawa Scale. Twelve studies involving 5057 patients met the inclusion criteria. Tandem ASCT was associated with a significantly higher CRR compared to single ASCT (HR 1.33, 95% CI 1.03-1.71, I2 = 15%), but no significant differences were observed in PFS (HR 0.75, 95% CI 0.42-1.34, I2 = 14%), OS (HR 0.60, 95% CI 0.33-1.10, I2 = 27%), or the ORR (RR 0.80, 95% CI 0.59-1.08, I2 = 33%). However, tandem ASCT was associated with a significantly higher risk of TRM (RR 1.78, 95% CI 1.00-3.18, I2 = 0%). Tandem ASCT improves the CRR but does not provide significant benefits in terms of PFS, OS, or ORR compared to single ASCT in patients with newly diagnosed MM. Moreover, tandem ASCT is associated with a higher risk of TRM. The decision to pursue tandem ASCT should be made on an individual basis, carefully weighing the potential benefits and risks in light of each patient's unique clinical situation. Future research should focus on identifying patient subgroups most likely to benefit from tandem ASCT and exploring strategies to optimize the efficacy and safety of this approach in the context of novel agent-based therapies.

13.
Front Neurol ; 15: 1403510, 2024.
Article in English | MEDLINE | ID: mdl-38751888
14.
Cont Lens Anterior Eye ; : 102172, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38806329

ABSTRACT

PURPOSE: To compare the efficacy and safety between traditional lens fitting and computer-aided fitting methods for orthokeratology (OrthoK) in the Chinese population. METHODS: A multi-center, examiner-masked, randomized controlled study was conducted with a one-year follow-up period, enrolling 280 participants with spherical equivalent (SE) ranging from -0.5D to -4.0D. Participants were assigned to either the computer-aided orthokeratology fitting group (trial group) or the traditional lens fitting group (control group) using stratified randomization based on age (8 to 13 years, 13 to 18 years, and ≥ 18 years) to ensure a minimum of 30 cases in each sub-age group. Ocular examinations included visual acuity, objective and subjective refraction, corneal endothelial cell density, corneal topography, intraocular pressure, axial length, and ocular health assessment. Successful lens-correction was defined as the residual refraction with the OK lens, which should not exceed ± 0.5D, and/or an uncorrected visual acuity of no worse than 0.1 logMAR. Statistical analysis involves t-tests, analysis of variance, and Chi-squared tests. RESULTS: 215 subjects were included in the statistical analysis (109 in the trial group and 106 in the control group). In both groups, compared to baseline data, the uncorrected visual acuity (UCVA) improved significantly, with SE reduced and central corneal curvature flattened greatly after wearing OrthoK lens (P < 0.05 for all). Compared to the control group, the trial group exhibited a higher successful rate in correcting UCVA (93.6 % vs. 84.0 %, P = 0.03) and slightly better correction in refraction (77.1 % vs. 66.0 %, P = 0.07) at 1-month follow-up. However, no significant differences were observed in the axial length elongation, corneal changes, or the incidence of adverse events between the two groups. CONCLUSION: These findings indicate the higher efficiency and slightly better performance in correcting myopia and improving UCVA of computer-aided lens fitting approach compared to the traditional one, but similar outcomes in controlling axial elongation.

15.
Comput Struct Biotechnol J ; 24: 322-333, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38690549

ABSTRACT

Data curation for a hospital-based cancer registry heavily relies on the labor-intensive manual abstraction process by cancer registrars to identify cancer-related information from free-text electronic health records. To streamline this process, a natural language processing system incorporating a hybrid of deep learning-based and rule-based approaches for identifying lung cancer registry-related concepts, along with a symbolic expert system that generates registry coding based on weighted rules, was developed. The system is integrated with the hospital information system at a medical center to provide cancer registrars with a patient journey visualization platform. The embedded system offers a comprehensive view of patient reports annotated with significant registry concepts to facilitate the manual coding process and elevate overall quality. Extensive evaluations, including comparisons with state-of-the-art methods, were conducted using a lung cancer dataset comprising 1428 patients from the medical center. The experimental results illustrate the effectiveness of the developed system, consistently achieving F1-scores of 0.85 and 1.00 across 30 coding items. Registrar feedback highlights the system's reliability as a tool for assisting and auditing the abstraction. By presenting key registry items along the timeline of a patient's reports with accurate code predictions, the system improves the quality of registrar outcomes and reduces the labor resources and time required for data abstraction. Our study highlights advancements in cancer registry coding practices, demonstrating that the proposed hybrid weighted neural-symbolic cancer registry system is reliable and efficient for assisting cancer registrars in the coding workflow and contributing to clinical outcomes.

16.
Cells ; 13(9)2024 Apr 28.
Article in English | MEDLINE | ID: mdl-38727294

ABSTRACT

Information on long-term effects of postovulatory oocyte aging (POA) on offspring is limited. Whether POA affects offspring by causing oxidative stress (OS) and mitochondrial damage is unknown. Here, in vivo-aged (IVA) mouse oocytes were collected 9 h after ovulation, while in vitro-aged (ITA) oocytes were obtained by culturing freshly ovulated oocytes for 9 h in media with low, moderate, or high antioxidant potential. Oocytes were fertilized in vitro and blastocysts transferred to produce F1 offspring. F1 mice were mated with naturally bred mice to generate F2 offspring. Both IVA and the ITA groups in low antioxidant medium showed significantly increased anxiety-like behavior and impaired spatial and fear learning/memory and hippocampal expression of anxiolytic and learning/memory-beneficial genes in both male and female F1 offspring. Furthermore, the aging in both groups increased OS and impaired mitochondrial function in oocytes, blastocysts, and hippocampus of F1 offspring; however, it did not affect the behavior of F2 offspring. It is concluded that POA caused OS and damaged mitochondria in aged oocytes, leading to defects in anxiety-like behavior and learning/memory of F1 offspring. Thus, POA is a crucial factor that causes psychological problems in offspring, and antioxidant measures may be taken to ameliorate the detrimental effects of POA on offspring.


Subject(s)
Behavior, Animal , Mitochondria , Oocytes , Oxidative Stress , Animals , Oocytes/metabolism , Mitochondria/metabolism , Female , Mice , Male , Ovulation , Anxiety/metabolism , Anxiety/pathology , Antioxidants/metabolism , Hippocampus/metabolism , Hippocampus/pathology , Blastocyst/metabolism , Cellular Senescence , Memory
17.
Expert Rev Mol Med ; 26: e7, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38602081

ABSTRACT

Trauma is a significant health issue that not only leads to immediate death in many cases but also causes severe complications, such as sepsis, thrombosis, haemorrhage, acute respiratory distress syndrome and traumatic brain injury, among trauma patients. Target protein identification technology is a vital technique in the field of biomedical research, enabling the study of biomolecular interactions, drug discovery and disease treatment. It plays a crucial role in identifying key protein targets associated with specific diseases or biological processes, facilitating further research, drug design and the development of treatment strategies. The application of target protein technology in biomarker detection enables the timely identification of newly emerging infections and complications in trauma patients, facilitating expeditious medical interventions and leading to reduced post-trauma mortality rates and improved patient prognoses. This review provides an overview of the current applications of target protein identification technology in trauma-related complications and provides a brief overview of the current target protein identification technology, with the aim of reducing post-trauma mortality, improving diagnostic efficiency and prognostic outcomes for patients.


Subject(s)
Brain Injuries, Traumatic , Humans , Brain Injuries, Traumatic/diagnosis , Brain Injuries, Traumatic/therapy , Hemorrhage
18.
Chem Commun (Camb) ; 60(40): 5334-5337, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38668748

ABSTRACT

A photoredox-catalyzed alkylarylation of activated alkenes via a radical C-C bond cleavage/Truce-Smiles rearrangement cascade is developed. The protocol features mild and redox-neutral conditions, broad substrate scope and excellent functional group compatibility, providing a facile and efficient approach to the long-chain distal keto-amides with all-carbon quaternary centers at the alpha position.

19.
Nat Commun ; 15(1): 3037, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38589472

ABSTRACT

The directional transformation of carbon dioxide (CO2) with renewable hydrogen into specific carbon-heavy products (C6+) of high value presents a sustainable route for net-zero chemical manufacture. However, it is still challenging to simultaneously achieve high activity and selectivity due to the unbalanced CO2 hydrogenation and C-C coupling rates on complementary active sites in a bifunctional catalyst, thus causing unexpected secondary reaction. Here we report LaFeO3 perovskite-mediated directional tandem conversion of CO2 towards heavy aromatics with high CO2 conversion (> 60%), exceptional aromatics selectivity among hydrocarbons (> 85%), and no obvious deactivation for 1000 hours. This is enabled by disentangling the CO2 hydrogenation domain from the C-C coupling domain in the tandem system for Iron-based catalyst. Unlike other active Fe oxides showing wide hydrocarbon product distribution due to carbide formation, LaFeO3 by design is endowed with superior resistance to carburization, therefore inhibiting uncontrolled C-C coupling on oxide and isolating aromatics formation in the zeolite. In-situ spectroscopic evidence and theoretical calculations reveal an oxygenate-rich surface chemistry of LaFeO3, that easily escape from the oxide surface for further precise C-C coupling inside zeolites, thus steering CO2-HCOOH/H2CO-Aromatics reaction pathway to enable a high yield of aromatics.

20.
Zhongguo Zhong Yao Za Zhi ; 49(4): 932-941, 2024 Feb.
Article in Chinese | MEDLINE | ID: mdl-38621900

ABSTRACT

This study explored the biosynthesis of bufadienolides(BDs) in Bufo bufo gargarizans to solve the dilemma of the decreasing resources of B. bufo gargarizans and provide a theoretical basis for the sustainable utilization of the resources. Ultra-high performance liquid chromatography-Orbitrap-mass spectrometry(UHPLC-Orbitrap-MS) was employed to detect the synthesis sites of BDs in B. bufo gargarizans, and the results were verified by desorption electrospray ionization-mass spectrometry imaging(DESI-MSI) and homogenate incubation experiments. BDs in B. bufo gargarizans had the highest content in the liver and the highest concentration in the gallbladder, in addition to the parotid gland and skin, which suggested that the liver could synthesize BDs. The results of DESI-MSI also showed that BDs were mainly enriched in the liver rather than the immature parotid gland. The incubation experiment of liver homogenates demonstrated the liver of B. bufo gargarizans had the ability to synthesize BDs. This study showed that the liver was a major organ for the synthesis of BDs in B. bufo gargarizans during metamorphosis, development, and growth, which provided strong theoretical support for the biosynthesis of BDs and the sustainable utilization of B. bufo gargarizans resources.


Subject(s)
Bufanolides , Animals , Bufo bufo , Tissue Distribution , Bufonidae , Spectrometry, Mass, Electrospray Ionization
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