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1.
Med Sci Monit ; 30: e943170, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39018268

ABSTRACT

BACKGROUND Tumor-infiltrating immune cells (TIICs) are implicated in the survival of ovarian cancer (OVCA) patients, but their prognostic significance in advanced or metastatic OVCA patients treated with neoadjuvant chemotherapy (NCAT) has not been well documented, particularly in the Chinese population. MATERIAL AND METHODS A total of 31 advanced or metastatic OVCA patients who underwent NACT were included. The density and positive rate of tumor-infiltrating immune cells (TIICs) within cancer cell nests and in cancer stroma were explored. The correlations of pre- or post-NACT TIICs with the efficacy of NACT and the changes in TIIC subpopulation with NACT were examined. RESULTS Compared with patients with partial benefit from NACT, significantly decreased pre-NACT intratumoral CD68⁺CD163⁺ cells (P=0.0043) and increased pre-NACT intratumoral CD56⁺ cells (P=0.038) were observed in patients with benefit. The high level of pre-NACT intratumoral CD68⁺CD163⁻ M1 macrophage (P=0.075) and stromal CD3⁺PD-1⁺ cells (P=0.085) predicated improved progression-free survival, respectively. Increased post-NACT stromal CD68⁺CD163⁻ M1 macrophage (P=0.01), stromal CD8⁺ T cells (P=0.073), and stromal CD8⁺PD-1⁺ cells (P=0.072) were associated with benefit from NACT. Moreover, NACT increased intratumoral CD3⁺ (P=0.031), CD8+ (P=0.031), and CD3⁺CD8⁺ cells (P=0.031). CONCLUSIONS High intratumoral CD68⁺CD163⁻, intratumoral CD56⁺ cells, and stromal CD3⁺PD-1⁺ cells pre-NACT predicted good prognosis. Intratumoral CD3⁺, CD8⁺, and CD3⁺CD8⁺ cells were increased after NACT. Evaluation of immune profiles may help to identify patients who might benefit from NACT and allow us to further stratify advanced or metastatic OVCA patients treated with NACT for disease management.


Subject(s)
Lymphocytes, Tumor-Infiltrating , Neoadjuvant Therapy , Ovarian Neoplasms , Humans , Female , Neoadjuvant Therapy/methods , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/immunology , Ovarian Neoplasms/pathology , Middle Aged , Prognosis , Retrospective Studies , Lymphocytes, Tumor-Infiltrating/immunology , Adult , Aged , Antigens, CD/metabolism , Antigens, Differentiation, Myelomonocytic/metabolism , Neoplasm Metastasis , Treatment Outcome , Tumor Microenvironment/immunology , China , Receptors, Cell Surface
2.
Radiat Oncol ; 19(1): 60, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38773605

ABSTRACT

BACKGROUND: The brachytherapy is an indispensable treatment for gynecological tumors, but the quality and efficiency of brachytherapy training for residents is still unclear. METHODS: An anonymous questionnaire was designed to collect information on gynecological brachytherapy (GBT) training for radiation oncology residents from 28 training bases in China. The questionnaire content was designed based on the principle of competency based medical education (CBME). The Likert scale was employed to evaluate self-reported competence and comprehension regarding GBT. A total of 132 senior residents were included in the final analysis. RESULTS: 53.79% (71/132) of senior residents had experience in performing image-guided GBT, whereas 76.52% (101/132) had observed the procedure during their standardized residency training. The proportion of senior residents who reported having the self-reported competence to independently complete the GBT was 78.03% for intracavity GBT, 75.00% for vaginal stump GBT, and 50.03% for interstitial GBT, respectively. The number of successful completion of Interstitial, intracavity and vaginal GBT was correlated with the self- confidence of trainees after standardized training. In particular, the independent completion of interstitial GBT for more than 20 cases was an independent factor for the self-reported competence of senior residents. During the training period, 50.76% and 56.82% of the residents had not participated in the specialized examinations and professional GBT courses. CONCLUSIONS: The study revealed that the self-confidence of residents to independently complete brachytherapy was relatively high, and the specialized curriculum setting and training process assessment for brachytherapy training still need to be strengthened in the future.


Subject(s)
Brachytherapy , Clinical Competence , Genital Neoplasms, Female , Internship and Residency , Radiation Oncology , Humans , Brachytherapy/methods , China , Genital Neoplasms, Female/radiotherapy , Radiation Oncology/education , Surveys and Questionnaires
3.
J Am Chem Soc ; 146(23): 16010-16019, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38805019

ABSTRACT

Flash Joule heating has emerged as an ultrafast, scalable, and versatile synthesis method for nanomaterials, such as graphene. Here, we experimentally and theoretically deconvolute the contributions of thermal and electrical processes to the synthesis of graphene by flash Joule heating. While traditional methods of graphene synthesis involve purely chemical or thermal driving forces, our results show that the presence of charge and the resulting electric field in a graphene precursor catalyze the formation of graphene. Furthermore, modulation of the current or the pulse width affords the ability to control the three-step phase transition of the material from amorphous carbon to turbostratic graphene and finally to ordered (AB and ABC-stacked) graphene and graphite. Finally, density functional theory simulations reveal that the presence of a charge- and current-induced electric field inside the graphene precursor facilitates phase transition by lowering the activation energy of the reaction. These results demonstrate that the passage of electrical current through a solid sample can directly drive nanocrystal nucleation in flash Joule heating, an insight that may inform future Joule heating or other electrical synthesis strategies.

4.
J Integr Plant Biol ; 66(7): 1500-1516, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38751028

ABSTRACT

Tapetum, the innermost layer of the anther wall, provides essential nutrients and materials for pollen development. Timely degradation of anther tapetal cells is a prerequisite for normal pollen development in flowering plants. Tapetal cells facilitate male gametogenesis by providing cellular contents after highly coordinated programmed cell death (PCD). Tapetal development is regulated by a transcriptional network. However, the signaling pathway(s) involved in this process are poorly understood. In this study, we report that a mitogen-activated protein kinase (MAPK) cascade composed of OsYDA1/OsYDA2-OsMKK4-OsMPK6 plays an important role in tapetal development and male gametophyte fertility. Loss of function of this MAPK cascade leads to anther indehiscence, enlarged tapetum, and aborted pollen grains. Tapetal cells in osmkk4 and osmpk6 mutants exhibit an increased presence of lipid body-like structures within the cytoplasm, which is accompanied by a delayed occurrence of PCD. Expression of a constitutively active version of OsMPK6 (CA-OsMPK6) can rescue the pollen defects in osmkk4 mutants, confirming that OsMPK6 functions downstream of OsMKK4 in this pathway. Genetic crosses also demonstrated that the MAPK cascade sporophyticly regulates pollen development. Our study reveals a novel function of rice MAPK cascade in plant male reproductive biology.


Subject(s)
Gene Expression Regulation, Plant , Mitogen-Activated Protein Kinases , Oryza , Plant Proteins , Pollen , Pollen/genetics , Pollen/growth & development , Oryza/genetics , Oryza/enzymology , Oryza/growth & development , Plant Proteins/metabolism , Plant Proteins/genetics , Mitogen-Activated Protein Kinases/metabolism , Mitogen-Activated Protein Kinases/genetics , MAP Kinase Signaling System , Fertility/physiology , Fertility/genetics , Mutation/genetics , Flowers/genetics , Flowers/physiology
5.
Biomol Biomed ; 2024 May 16.
Article in English | MEDLINE | ID: mdl-38761408

ABSTRACT

A platinum-based concurrent chemoradiotherapy (CCRT) is the standard treatment for refractory cervical cancer (CC). However, the recurrence of disease and the occurrence of metastasis remain prevalent. We observed the long-term efficacy and safety of bevacizumab combined with neoadjuvant chemotherapy (NACT) and CCRT in refractory CC. A total of 62 patients with refractory CC were enrolled in this study from January 2016 to December 2019. The NACT regimen included bevacizumab (7.5 mg/kg), docetaxel (75 mg/m2), and cisplatin (75 mg/m2), administered tri-weekly for 2 cycles. The CCRT regimen included bevacizumab (7.5 mg/kg) and cisplatin (75 mg/m2), administered tri-weekly for 2 cycles. A dose of 45-50 Gy was prescribed for external beam radiotherapy (EBRT), while 30-35 Gy in 4-5 fractions was prescribed for brachytherapy (BT). Among the patients, 21 patients (33.9%) were at stages IIB-IIIB, 8 patients (12.9%) were at stage IIIC1, 19 patients (30.6%) were at stage IIIC2, and 14 patients (22.6%) were at stage IVB. Pelvic, para-aortic, supraclavicular, and inguinal lymph node metastases were discovered in 41 patients (66.1%). The median follow-up was 49.8 months (12.3-82.7 months). The median tumor volumes pre-treatment, after NACT, and before BT were 84.64 ± 53.15 cm3, 1.64 ± 13.15 cm3, and 0 ± 1.5 cm3, respectively. Complete clinical response (cCR) rates after NACT and EBRT were 35.5% and 66.1%, respectively. Four years after the diagnosis, the overall survival (OS) rate was 78.6%, the local region-free survival (LRFS) rate was 91.3%, the disease-free survival (DFS) rate was 70.6%, and the distant metastasis-free survival (DMFS) rate was 81.4%. A total of 29 patients (46.8%) experienced grade 3/4 hematological toxicity, 3 patients (4.8%) experienced grade 3 gastrointestinal toxicities, and none experienced grade 5 adverse events. Bevacizumab combined with NACT and CCRT significantly improved cCR and OS in refractory CC with acceptable toxicity.

6.
Front Surg ; 11: 1365498, 2024.
Article in English | MEDLINE | ID: mdl-38596166

ABSTRACT

Objective: This study aims to investigate the treatment strategies for lumbar brucellar spondylitis by comparing the outcomes of pure pharmacological treatment with diseased intervertebral fixation fusion, with or without lesion clearance. Methods: A total of 157 patients with lumbar brucellar spondylitis were categorized into three groups: Group A (52 cases) received pure pharmacological treatment, Group B (53 cases) underwent posterior vertebral fixation fusion, and Group C (52 cases) received posterior (or anterior) lesion clearance followed by posterior vertebral fixation fusion. Clinical data were analyzed, and the efficacy of the three treatment methods was evaluated. Results: The surgical groups showed better outcomes at various time points compared to the pharmacological treatment group (P < 0.05). The pure fixation group outperformed the lesion clearance fusion group during the perioperative period (P < 0.05). The ESR, CRP, ODI scores, imaging evaluation and complications of the lesion clearance followed by fixation group were all better than those of the other two groups (P < 0.05). Surgical treatment groups showed no statistically significant difference in VAS scores (P > 0.05), and both were superior to the pharmacological treatment group. There were no statistically significant differences in clinical efficacy among the three groups at the last follow-up. Conclusion: Surgical treatment achieves early recovery goals compared to pharmacological treatment for brucellar spondylitis. However, individualized treatment principles should guide surgical decisions to select the most suitable approach for patients.

7.
Bioresour Technol ; 399: 130524, 2024 May.
Article in English | MEDLINE | ID: mdl-38492652

ABSTRACT

In this study, the effect of hydrothermal carbonation (HTC) on the pyrolysis behavior and the distribution of nutrients and metal species of waste-activated sludge (WAS) was investigated. Results showed that the pyrolysis activation energy range of WAS decreased from 11 to 57 kJ/mol to 10-36 kJ/mol when the hydrothermal carbonization was at 160 °C. As indicated by thermodynamic parameters, the hydrothermal carbonization process reduces the pyrolysis reaction activity of the hydrochar. The results of the chemical analysis indicate that hydrothermal carbonization significantly enhances the release of phosphorus and nitrogen, with maximum recovery at a temperature of 200 °C. The standard measurement and testing protocol revealed that hydrothermal carbonization increased the content of non-apatite inorganic P fraction in hydrochar and enhanced the availability of P. Heavy metal analysis shows that hydrothermal carbonization can strengthen the stability of heavy metals in WAS.


Subject(s)
Metals, Heavy , Sewage , Sewage/chemistry , Pyrolysis , Temperature , Nutrients , Carbon/chemistry
8.
Polymers (Basel) ; 16(3)2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38337329

ABSTRACT

Polyurea has gained significant attention in recent years as a functional polymer material, specifically regarding blast and impact protection. The molecular structure of polyurea is characterized by the rapid reaction between isocyanate and the terminal amine component, and forms an elastomeric copolymer that enhances substrate protection against blast impact and fragmentation penetration. At the nanoscale, a phase-separated microstructure emerges, with dispersed hard segment microregions within a continuous matrix of soft segments. This unique microstructure contributes to the remarkable mechanical properties of polyurea. To maximize these properties, it is crucial to analyze the molecular structure and explore methods like formulation optimization and the incorporation of reinforcing materials or fibers. Current research efforts in polyurea applications for protective purposes primarily concentrate on construction, infrastructure, military, transportation and industrial products and facilities. Future research directions should encompass deliberate formulation design and modification, systematic exploration of factors influencing protective performance across various applications and the integration of numerical simulations and experiments to reveal the protective mechanisms of polyurea. This paper provides an extensive literature review that specifically examines the utilization of polyurea for blast and impact protection. It encompasses discussions on material optimization, protective mechanisms and its applications in blast and impact protection.

9.
Cell Death Dis ; 15(1): 9, 2024 01 05.
Article in English | MEDLINE | ID: mdl-38182571

ABSTRACT

Chromatin accessibility plays important roles in revealing the regulatory networks of gene expression, while its application in bladder cancer is yet to be fully elucidated. Chloride intracellular channel 3 (CLIC3) protein has been reported to be associated with the progression of some tumors, whereas the specific mechanism of CLIC3 in tumor remains unclear. Here, we screened for key genes in bladder cancer through the identification of transcription factor binding site clustered region (TFCR) on the basis of chromatin accessibility and TF motif. CLIC3 was identified by joint profiling of chromatin accessibility data with TCGA database. Clinically, CLIC3 expression was significantly elevated in bladder cancer and was negatively correlated with patient survival. CLIC3 promoted the proliferation of bladder cancer cells by reducing p21 expression in vitro and in vivo. Mechanistically, CLIC3 interacted with NAT10 and inhibited the function of NAT10, resulting in the downregulation of ac4C modification and stability of p21 mRNA. Overall, these findings uncover an novel mechanism of mRNA ac4C modification and CLIC3 may act as a potential therapeutic target for bladder cancer.


Subject(s)
Urinary Bladder Neoplasms , Humans , Chloride Channels/genetics , Chromatin , N-Terminal Acetyltransferases , RNA, Messenger/genetics , Urinary Bladder , Urinary Bladder Neoplasms/genetics
10.
BMJ Open ; 13(10): e075242, 2023 10 28.
Article in English | MEDLINE | ID: mdl-37898488

ABSTRACT

INTRODUCTION: Radical surgery including mediastinal lymph node dissection is the standard treatment for early-stage non-small cell lung cancer (NSCLC). About 50% lung nodules are pure ground glass or part-solid nodules, which are predominantly clinical stage IA NSCLC. Non-solid nodules rarely develop mediastinal lymph node metastasis. METHOD AND ANALYSIS: A phase III study was started in China to evaluate the non-inferiority in overall survival of spared mediastinal lymph node dissection compared with mediastinal lymph node dissection in stage IA NSCLC. A total of 1362 patients will be enrolled from 4 institutions in 2-3 years. The second endpoints are relapse-free survival and perioperative data, including duration of hospitalisation, duration of chest tube placement, operation time, blood loss. ETHICS AND DISSEMINATION: This protocol has been reviewed and approved by the Clinical Research Review Board of Tianjin Medical University Cancer Institute and Hospital. The findings will be disseminated in peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT04631770.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Lung Neoplasms/pathology , Lymph Node Excision/methods , Lymph Nodes/surgery , Lymph Nodes/pathology , Multicenter Studies as Topic , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , Randomized Controlled Trials as Topic , Retrospective Studies , Clinical Trials, Phase III as Topic
11.
Cell Commun Signal ; 21(1): 266, 2023 09 28.
Article in English | MEDLINE | ID: mdl-37770930

ABSTRACT

Integrins are transmembrane receptors that possess distinct ligand-binding specificities in the extracellular domain and signaling properties in the cytoplasmic domain. While most integrins have a short cytoplasmic tail, integrin ß4 has a long cytoplasmic tail that can indirectly interact with the actin cytoskeleton. Additionally, 'inside-out' signals can induce integrins to adopt a high-affinity extended conformation for their appropriate ligands. These properties enable integrins to transmit bidirectional cellular signals, making it a critical regulator of various biological processes.Integrin expression and function are tightly linked to various aspects of tumor progression, including initiation, angiogenesis, cell motility, invasion, and metastasis. Certain integrins have been shown to drive tumorigenesis or amplify oncogenic signals by interacting with corresponding receptors, while others have marginal or even suppressive effects. Additionally, different α/ß subtypes of integrins can exhibit opposite effects. Integrin-mediated signaling pathways including Ras- and Rho-GTPase, TGFß, Hippo, Wnt, Notch, and sonic hedgehog (Shh) are involved in various stages of tumorigenesis. Therefore, understanding the complex regulatory mechanisms and molecular specificities of integrins are crucial to delaying cancer progression and suppressing tumorigenesis. Furthermore, the development of integrin-based therapeutics for cancer are of great importance.This review provides an overview of integrin-dependent bidirectional signaling mechanisms in cancer that can either support or oppose tumorigenesis by interacting with various signaling pathways. Finally, we focus on the future opportunities for emergent therapeutics based on integrin agonists. Video Abstract.


Subject(s)
Hedgehog Proteins , Neoplasms , Humans , Integrins/metabolism , Signal Transduction , Carcinogenesis
12.
Nat Commun ; 14(1): 4266, 2023 Jul 17.
Article in English | MEDLINE | ID: mdl-37460538

ABSTRACT

Durability is one prerequisite for material application. Photoelectrochemical decomposition of seawater is a promising approach to produce clean hydrogen by using solar energy, but it always faces the problem of serious Cl- corrosion. We find that the main deactivation mechanism of the photoanode is oxide surface reconstruction accompanied by the coordination of Cl- during seawater splitting, and the stability of the photoanode can be effectively improved by enhancing the metal-oxygen interaction. Taking the metastable ß-Fe2O3 photoanode as an example, Sn added to the lattice can enhance the M-O bonding energy and hinder the transfer of protons to lattice oxygen, thereby inhibiting excessive surface hydration and Cl- coordination. Therefore, the bare Sn/ß-Fe2O3 photoanode delivers a record durability for photoelectrochemical seawater splitting over 3000 h.

13.
FASEB J ; 37(3): e22810, 2023 03.
Article in English | MEDLINE | ID: mdl-36786718

ABSTRACT

Technology at the single-cell level has advanced dramatically in characterizing molecular heterogeneity. These technologies have enabled cell subtype diversity to be seen in all tissues, including atherosclerotic plaques. Critical in atherosclerosis pathogenesis and progression are macrophages. Previous studies have only determined macrophage phenotypes within the plaque, mainly by bulk analysis. However, recent progress in single-cell technologies now enables the comprehensive mapping of macrophage subsets and phenotypes present in plaques. In this review, we have updated and discussed the definition and classification of macrophage subsets in mice and humans using single-cell RNA sequencing. We summarized the different classification methods and perspectives: traditional classification with an updated scoring system, inflammatory macrophages, foamy macrophages, and atherosclerotic-resident macrophages. In addition, some special types of macrophages were identified by specific markers, including IFN-inducible and cavity macrophages. Furthermore, we discussed macrophage subset-specific markers and their functions. In the future, these novel insights into the characteristics and phenotypes of these macrophage subsets within atherosclerotic plaques can provide additional therapeutic targets for cardiovascular diseases.


Subject(s)
Atherosclerosis , Plaque, Atherosclerotic , Humans , Mice , Animals , Plaque, Atherosclerotic/metabolism , Atherosclerosis/metabolism , Macrophages/metabolism , Phenotype , Sequence Analysis, RNA/methods
14.
Ecotoxicol Environ Saf ; 251: 114509, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36621032

ABSTRACT

Bacillus subtilis as microbial fertilizers contribute to avoiding the harmful effects of traditional agricultural fertilizers and pesticides. However, there are many restrictions on the practical application of fertilizers. In this study, microbial biochar formulations (BCMs) were prepared by loading biochar with B. subtilis SL-44. Pot experiments were conducted to evaluate the effects of the BCMs on soil fertility, Fusarium wilt control, and radish plant growth. The application of BCMs dramatically improved soil properties and favored plant growth. Compared with SL-44 and biochar treatments, the BCMs treatments increased radish plant physical-chemical properties and activities of several enzymes in the soil. What's more, Fusarium wilt incidence had decreased by 59.88%. In addition, the BCMs treatments exhibited a significant increase in the abundance of bacterial genera in the rhizosphere soil of radish. Therefore, this study demonstrated that BCMs may be an eco-friendly strategy for improving soil fertility, reducing Fusarium wilt, and promoting radish plant growth.


Subject(s)
Fusarium , Raphanus , Soil/chemistry , Bacillus subtilis , Fertilizers/analysis , Soil Microbiology , Rhizosphere
15.
Neuron ; 111(3): 387-404.e8, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36476978

ABSTRACT

Precise monitoring of internal temperature is vital for thermal homeostasis in mammals. For decades, warm-sensitive neurons (WSNs) within the preoptic area (POA) were thought to sense internal warmth, using this information as feedback to regulate body temperature (Tcore). However, the cellular and molecular mechanisms by which WSNs measure temperature remain largely undefined. Via a pilot genetic screen, we found that silencing the TRPC4 channel in mice substantially attenuated hypothermia induced by light-mediated heating of the POA. Loss-of-function studies of TRPC4 confirmed its role in warm sensing in GABAergic WSNs, causing additional defects in basal temperature setting, warm defense, and fever responses. Furthermore, TRPC4 antagonists and agonists bidirectionally regulated Tcore. Thus, our data indicate that TRPC4 is essential for sensing internal warmth and that TRPC4-expressing GABAergic WSNs function as a novel cellular sensor for preventing Tcore from exceeding set-point temperatures. TRPC4 may represent a potential therapeutic target for managing Tcore.


Subject(s)
Body Temperature Regulation , Body Temperature , Mice , Animals , Body Temperature/physiology , Body Temperature Regulation/physiology , Hypothalamus , Preoptic Area/physiology , GABAergic Neurons , Mammals
16.
Front Plant Sci ; 14: 1324401, 2023.
Article in English | MEDLINE | ID: mdl-38333039

ABSTRACT

Tomatoes are susceptible to damage from cold temperatures in all stages of growth. Therefore, it is important to identify genetic resources and genes that can enhance tomato's ability to tolerate cold. In this study, a population of 223 tomato accessions was used to identify the sensitivity or tolerance of plants to cold stress. Transcriptome analysis of these accessions revealed that SUS3, a member of the sucrose synthase gene family, was induced by cold stress. We further investigated the role of SUS3 in cold stress by overexpression (OE) and RNA interference (RNAi). Compared with the wild type, SUS3-OE lines accumulated less MDA and electrolyte leakage and more proline and soluble sugar, maintained higher activities of SOD and CAT, reduced superoxide radicals, and suffered less membrane damage under cold. Thus, our findings indicate that SUS3 plays a crucial role in the response to cold stress. This study indicates that SUS3 may serve as a direct target for genetic engineering and improvement projects, which aim to augment the cold tolerance of tomato crops.

17.
RSC Adv ; 12(53): 34268-34281, 2022 Nov 29.
Article in English | MEDLINE | ID: mdl-36545590

ABSTRACT

Because of its excellent performance, methyl hexahydrophthalic anhydride (MHHPA) is a new anhydride-based epoxy resin curing agent after methyl tetrahydrophthalic anhydride (MTHPA). To improve the activity and stability of conventional RANEY® nickel catalysts in the catalytic hydrogenation of MTHPA to MHHPA reaction, RANEY® nickel encapsulated with porous Al2O3 and alumina-supported Ni-Ru bimetallic catalysts were designed and synthesized in this study. The physicochemical properties and surface reactions over the catalysts were characterized by N2 adsorption and desorption, X-ray diffraction (XRD), hydrogen temperature-programmed reduction/desorption (H2-TPR/TPD), X-ray photoelectron spectroscopy (XPS), scanning electronic microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and in situ diffuse reflectance infrared Fourier transformations spectroscopy (DRIFTS). The kinetic model of MTHPA hydrogenation over NiRu/Al was established and the parameters were estimated using the least-square method. The results showed that the encapsulation of porous Al2O3 on the surface of RANEY® nickel enhanced the stability of the Ni skeleton and the adsorption ability of the reactant molecules, which improved its activity for the hydrogenation reaction. The introduction of Ru improved the dispersion and stability of metallic Ni, which greatly increased the conversion ability towards MTHPA hydrogenation, but it had a trend to cause C[double bond, length as m-dash]C bond transfer at lower temperatures, increasing the hydrogenation difficulties. The kinetic results based on Ni-Ru bimetallic catalyst showed that the MTHPA hydrogenation reaction rate was first-order with respect to MTHPA concentration and 0.5-order with respect to hydrogen partial pressure, and the apparent activation energy of the hydrogenation reaction was 37.02 ± 2.62 kJ mol-1.

18.
Nat Chem Biol ; 18(11): 1196-1203, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35982227

ABSTRACT

Adhesion G protein-coupled receptors are elusive in terms of their structural information and ligands. Here, we solved the cryogenic-electron microscopy (cryo-EM) structure of apo-ADGRG2, an essential membrane receptor for maintaining male fertility, in complex with a Gs trimer. Whereas the formations of two kinks were determinants of the active state, identification of a potential ligand-binding pocket in ADGRG2 facilitated the screening and identification of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate and deoxycorticosterone as potential ligands of ADGRG2. The cryo-EM structures of DHEA-ADGRG2-Gs provided interaction details for DHEA within the seven transmembrane domains of ADGRG2. Collectively, our data provide a structural basis for the activation and signaling of ADGRG2, as well as characterization of steroid hormones as ADGRG2 ligands, which might be used as useful tools for further functional studies of the orphan ADGRG2.


Subject(s)
Receptors, G-Protein-Coupled , Signal Transduction , Humans , Male , Cryoelectron Microscopy , Dehydroepiandrosterone Sulfate , Desoxycorticosterone , Ligands , Receptors, G-Protein-Coupled/chemistry
19.
Proc Natl Acad Sci U S A ; 119(36): e2205562119, 2022 09 06.
Article in English | MEDLINE | ID: mdl-36037332

ABSTRACT

Hydrogen peroxide (H2O2) molecules play important roles in many green chemical reactions. However, the high activation energy limits their application efficiency, and there is still huge controversy about the activation path of H2O2 molecules over the presence of *OOH intermediates. Here, we confirmed the formation of the key species *OOH in the heterogeneous system, via in situ shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS), isotope labeling, and theoretical calculation. In addition, we found that compared with *H2O2, *OOH was more conducive to the charge transfer behavior with the catalyst and the activation of an O-O bond. Furthermore, we proposed to improve the local coordination structure and electronic density of the YFeO3 catalyst by regulating the surface relaxation with Ti modification so as to reduce the activation barrier of H2O2 and to improve the production efficiency of •OH. As a result, the kinetics rates of the Fenton-like (photo-Fenton) reaction had been significantly increased several times. The •OH free radical activity mechanism and molecular transformation pathways of 4-chloro phenol (4-CP) were also revealed. This may provide a clearer vision for the further study of H2O2 activation and suggest a means of designing catalysts for efficient H2O2 activation.


Subject(s)
Hydrogen Peroxide , Photochemical Processes , Catalysis , Hydrogen Peroxide/chemistry , Iron/chemistry , Light , Phenol
20.
Front Neural Circuits ; 16: 891825, 2022.
Article in English | MEDLINE | ID: mdl-35814484

ABSTRACT

Single-photon-based head-mounted microscopy is widely used to record the brain activities of freely-moving animals. However, during data acquisition, the free movement of animals will cause shaking in the field of view, which deteriorates subsequent neural signal analyses. Existing motion correction methods applied to calcium imaging data either focus on offline analyses or lack sufficient accuracy in real-time processing for single-photon data. In this study, we proposed an open-source real-time motion correction (RTMC) plug-in for single-photon calcium imaging data acquisition. The RTMC plug-in is a real-time subpixel registration algorithm that can run GPUs in UCLA Miniscope data acquisition software. When used with the UCLA Miniscope, the RTMC algorithm satisfies real-time processing requirements in terms of speed, memory, and accuracy. We tested the RTMC algorithm by extending a manual neuron labeling function to extract calcium signals in a real experimental setting. The results demonstrated that the neural calcium dynamics and calcium events can be restored with high accuracy from the calcium data that were collected by the UCLA Miniscope system embedded with our RTMC plug-in. Our method could become an essential component in brain science research, where real-time brain activity is needed for closed-loop experiments.


Subject(s)
Calcium , Microscopy , Algorithms , Animals , Brain/diagnostic imaging , Brain/physiology , Motion
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