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1.
Phytomedicine ; 132: 155851, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39018943

RESUMO

BACKGROUND: Evodiamine (EVO) is one of the primary components of Evodia rutaecarpa and has been found to have a positive therapeutic effect on various digestive system diseases. However, no systematic review has been conducted on the research progress and mechanisms of EVO in relation to digestive system diseases, and its toxicity. PURPOSE: This study aimed to provide a reference for future research in this field. STUDY DESIGN: A systematic review and meta-analysis of the research progress, mechanisms, and toxicity of EVO in the treatment of digestive system diseases. METHODS: Five electronic databases were utilized to search for relevant experiments. We conducted a comprehensive review and meta-analysis of the pertinent literature following the guidelines of Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA). RESULTS: EVO's animal experiments in digestive system diseases primarily focus on colorectal cancer, gastric ulcers, liver cancer, liver fibrosis, ulcerative colitis, colitis-associated cancer, and functional gastrointestinal disorders. EVO also has positive effects on pancreatic cancer, radiation enteritis, gastric cancer, tongue squamous cancer, hepatitis B, oral cancer, and esophageal cancer in vivo. EVO's in cellular experiments primarily focus on SGC7901, HT29, HCT-116, and HepG2 cells. EVO also exhibits positive effects on SW480, LoVo, BGC-823, AGS, COLO-205, MKN45, SMMC-7721, Bel-7402, QGY7-701, PANC-1, SW1990, BxPC-3, HSC4, MC3, HONE1, and CNE1 cells in vitro. The potential common pathways include TGF-ß, PI3K-AKT, Wnt, ErbB, mTOR, MAPK, HIF-1, NOD-like receptor, NF-κB, VEGF, JAK-STAT, AMPK, Toll-like receptor, EGFR, Ras, TNF, AGE-RAGE, Relaxin, FoxO, IL-17, Hippo, and cAMP. The mechanisms of EVO on ulcerative colitis, gastric cancer, and HCT116 cells are still controversial in vivo. EVO may have a bidirectional regulatory effect on functional gastrointestinal disorders through calcium signaling. The mechanisms of EVO on HCT116, HT29, SW480, AGS, COLO-205, and SW1990 cells are still controversial in vitro. The question of whether EVO has obvious toxicity is controversial. CONCLUSION: In both cellular and animal experiments, EVO has demonstrated positive impacts on digestive system diseases. Nevertheless, additional in vivo and in vitro research is required to confirm the beneficial effects and mechanisms of EVO on digestive system diseases, as well as its potential toxicity.

2.
Anal Chem ; 96(28): 11383-11389, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38946419

RESUMO

Apurinic/apyrimidinic endonuclease 1 (APE1), as a vital base excision repair enzyme, is essential for maintaining genomic integrity and stability, and its abnormal expression is closely associated with malignant tumors. Herein, we constructed an electrochemiluminescence (ECL) biosensor for detecting APE1 activity by combining nanoconfined ECL silver nanoclusters (Ag NCs) with X-shaped DNA recognizer-triggered cascade amplification. Specifically, the Ag NCs were prepared and confined in the glutaraldehyde-cross-linked chitosan hydrogel network using the one-pot method, resulting in a strong ECL response and exceptional stability in comparison with discrete Ag NCs. Furthermore, the self-assembled X-shaped DNA recognizers were designed for APE1 detection, which not only improved reaction kinetics due to the ordered arrangement of recognition sites but also achieved high sensitivity by utilizing the recognizer-triggered cascade amplification of strand displacement amplification (SDA) and DNAzyme catalysis. As expected, this biosensor achieved sensitive ECL detection of APE1 in the range of 1.0 × 10-3 U·µL-1 to 1.0 × 10-10 U·µL-1 with the detection limit of 2.21 × 10-11 U·µL-1, rendering it a desirable approach for biomarker detection.


Assuntos
Técnicas Biossensoriais , DNA Liase (Sítios Apurínicos ou Apirimidínicos) , Técnicas Eletroquímicas , Medições Luminescentes , Nanopartículas Metálicas , Prata , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/análise , Prata/química , Humanos , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , Técnicas Biossensoriais/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , DNA/química , Limite de Detecção , DNA Catalítico/química , DNA Catalítico/metabolismo
3.
J Chromatogr A ; 1730: 465150, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38991603

RESUMO

The precise determination of polypeptide antibiotics (PPTs) in foods has been always challenging because of the interference of various endogenous peptides in complex matrix. Herin, a novel large-pore covalent organic framework (TABPT-SPDA-COF) with accessible pore size of 7.9 nm was synthesized as a solid phase extraction (SPE) absorbent for efficiently enriching four PPTs existed in foods originating from animals. The parameters of SPE process were systematically optimized. Subsequently, four PPTs were determined by UHPLC-MS/MS. Under the optimal conditions, TABPT-SPDA-COF shows outstanding enrichment capacity for PPTs in contrast to commercial absorbents ascribed to size selectivity and multiple interaction effects. The method exhibits excellent linear range (0.005-100 ng mL-1), satisfactory limits of detection (0.1 pg mL-1) as well as relative recoveries (86.2-116 %). This work offers a practicable platform to monitor trace PPTs from complex animal-derived foodstuffs.

4.
Front Immunol ; 15: 1403272, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39040102

RESUMO

Introduction: Granulocytic myeloid-derived suppressor cells (G-MDSCs) show fast recovery following allogeneic hematopoietic stem cell transplantation (allo-HSCT) constituting the major part of peripheral blood in the early phase. Although G-MDSCs mediate immune suppression through multiple mechanisms, they may also promote inflammation under specific conditions. Methods: G-MDSCs were isolated from 82 patients following allo-HSCT within 90 days after allo-HSCT, and their interactions with autologous CD3+ T-cells were examined. T-cell proliferation was assessed by flow cytometry following CFSE staining, while differentiation and interferon-γ secretion were characterized using chemokine receptor profiling and ELISpot assays, respectively. NK cell cytotoxicity was evaluated through co-culture with K562 cells. An aGVHD xenogeneic model in humanized mice was employed to study the in vivo effects of human leukocytes. Furthermore, transcriptional alterations in G-MDSCs were analyzed via RNA sequencing to investigate functional transitions. Results: G-MDSCs promoted inflammation in the early-stage, by facilitating cytokine secretion and proliferation of T cells, as well as their differentiation into pro-inflammatory T helper subsets. At day 28, patients with a higher number of G-MDSCs exhibited an increased risk of developing grades II-IV aGvHD. Besides, adoptive transfer of G-MDSCs from patients at day 28 into humanized mice exacerbated aGvHD. However, at day 90, G-MDSCs led to immunosuppression, characterized by upregulated expression of indoleamine 2,3-dioxygenase gene and interleukin-10 secretion, coupled with the inhibition of T cell proliferation. Furthermore, transcriptional analysis of G-MDSCs at day 28 and day 90 revealed that 1445 genes were differentially expressed. These genes were associated with various pathways, revealing the molecular signatures of early post-transplant differentiation in G-MDSCs. In addition, genes linked to the endoplasmic reticulum stress were upregulated in patients without aGvHD. The acquisition of immunosuppressive function by G-MDSCs may depend on the activation of CXCL2 and DERL1 genes. Conclusion: Our findings revealed the alteration in the immune characteristics of G-MDSCs within the first 90 days post-allo-HSCT. Moreover, the quantity of G-MDSCs at day 28 may serve as a predictive indicator for the development of aGvHD.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Células Supressoras Mieloides , Transplante Homólogo , Humanos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Animais , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/metabolismo , Camundongos , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Antígenos HLA-DR/metabolismo , Antígenos HLA-DR/imunologia , Antígenos HLA-DR/genética , Doença Enxerto-Hospedeiro/imunologia , Inflamação/imunologia , Adulto Jovem , Granulócitos/imunologia , Granulócitos/metabolismo , Adolescente , Antígeno CD11b/metabolismo , Antígeno CD11b/imunologia
5.
Toxicon ; 247: 107850, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38971137

RESUMO

BACKGROUND: Enterobacter cloacae insecticidal proteins have been reported to kill Galleria mellonella larvae through affecting their midgut microbiome. However, the mechanisms involved remain unclear. Here we aim to investigate how the insecticidal proteins act on the midgut Duox-ROS system and microbial community of G. mellonella larvae. METHODS: Reverse transcription qPCR and fluorescence probes were utilized to assess the Duox expression levels and to evaluate quantitative changes of the ROS levels. Sequencing of the 16S rRNA gene sequences of the midgut bacteria of G. mellonella larvae was conducted for further analyses of bacterial diversity, composition, and abundance. RESULTS: After the injection of the insecticidal proteins, the Duox expression levels first increased within 28 h, then dramatically peaked at 36 h, and slowly decreased thereafter. Simultaneously, the ROS levels increased significantly at 36 h, peaked at 48 h, and rapidly declined to the normal level at 60 h. Responsive to the change of the ROS levels, the structure of the midgut microbial community was altered substantially, compared to that of the untreated larvae. The relative abundance of Enterobacteriaceae and other specific pathogenic bacteria increased significantly, whereas that of Lactobacillus decreased sharply. Importantly, notable shifts were observed in the crucial midgut predicted metabolic functions, including membrane transportation, carbohydrate metabolism, and amino acid metabolism. CONCLUSION: Insecticidal proteins of E. cloacae kill G. mellonella larvae mainly through generation of high oxidative stress, alterations of the midgut microbial community and function, and damage to the physiological functions. These findings provide insights into the inhibition mechanism of E. cloacae insecticidal proteins to G. mellonella larvae.

6.
Biosens Bioelectron ; 262: 116547, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38968775

RESUMO

5-formylcytosine (5 fC) and 5-carboxylcytosine (5caC) serve as key intermediates in DNA demethylation process with significant implications for gene regulation and disease progression. In this study, we introduce a novel electrochemical sensing platform specifically designed for the sensitive and selective detection of 5 fC and 5caC in DNA. Protein A-modified magnetic beads (ProtA-MBs) coupled with specific antibodies facilitate the immunorecognition and enrichment of these modified bases. Signal amplification is achieved through several chemical reactions involving the interaction between N3-kethonaxl and guanine, copper-free click chemistry for the attachment of dibenzocyclooctyne (DBCO)-Biotin, and the subsequent recognition by streptavidin-conjugated horseradish peroxidase (SA-HRP). The assay's readout is performed on a disposable laser-induced graphene (LIG) electrode, modified with the bead-antibody-DNA complex in a magnetic field, and analyzed using differential pulse voltammetry in a system employing hydroquinone (HQ) as the redox mediator and H2O2 as the substrate. This immunosensor displayed excellent sensitivity, with detection limits of 14.8 fM for 5 fC across a 0.1-1000 pM linear range and 87.4 fM for 5caC across a 0.5-5000 pM linear range, and maintained high selectivity even in the presence of interferences from other DNA modifications. Successful application in quantifying 5 fC and 5caC in genomic DNA from cell extracts, with recovery rates between 97.7% to 102.9%, underscores its potential for clinical diagnostics. N3-kethoxal was used for the first time in an electrochemical sensor. This work not only broadens the toolkit for detecting DNA modifications but also provides a fresh impetus for the development of point-of-care testing (POCT) technologies.


Assuntos
Técnicas Biossensoriais , Citosina , DNA , Técnicas Eletroquímicas , Limite de Detecção , DNA/química , Técnicas Eletroquímicas/métodos , Citosina/química , Citosina/análogos & derivados , Humanos , Imunoensaio/métodos , Imunoensaio/instrumentação , Grafite/química
7.
J Am Coll Emerg Physicians Open ; 5(3): e13190, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38827500

RESUMO

Objective: To analyze the risk factors associated with intubated critically ill patients in the emergency department (ED) and develop a prediction model by machine learning algorithms. Methods: This study was conducted in an academic tertiary hospital in Hangzhou, China. Critically ill patients admitted to the ED were retrospectively analyzed from May 2018 to July 2022. The demographic characteristics, distribution of organ dysfunction, parameters for different organs' examination, and status of mechanical ventilation were recorded. These patients were assigned to the intubation and non-intubation groups according to ventilation support. We used the eXtreme Gradient Boosting (XGBoost) algorithm to develop the prediction model and compared it with other algorithms, such as logistic regression, artificial neural network, and random forest. SHapley Additive exPlanations was used to analyze the risk factors of intubated critically ill patients in the ED. Results: Of 14,589 critically ill patients, 10,212 comprised the training group and 4377 comprised the test group; 2289 intubated patients were obtained from the electronic medical records. The mean age, mean scores of vital signs, parameters of different organs, and blood oxygen examination results differed significantly between the two groups (p < 0.05). The white blood cell count, international normalized ratio, respiratory rate, and pH are the top four risk factors for intubation in critically ill patients. Based on the risk factors in different predictive models, the XGBoost model showed the highest area under the receiver operating characteristic curve (0.84) for predicting ED intubation. Conclusions: For critically ill patients in the ED, the proposed model can predict potential intubation based on the risk factors in the clinically predictive model.

8.
Behav Sci (Basel) ; 14(6)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38920776

RESUMO

People with generalized anxiety disorder tend to have sleep problems, and studies have found correlations between metacognition, rumination, and sleep, but it is unclear how metacognition and rumination work in people with a tendency towards generalized anxiety disorder. The goal of this paper is to investigate the correlation between metacognition, rumination, and sleep in university students with a tendency towards generalized anxiety disorder, and the mediating role of rumination in the effect of metacognition on sleep. The Generalized Anxiety Disorder Scale (GAD-7), the Meta-Cognition Questionnaire (MCQ-30), the Ruminative Responses Scale (RRS), and the Insomnia Severity Index (ISI) were used to investigate and psychometrically measure 566 university students in Anyang Normal College. The results of correlation analysis showed significant positive correlations between metacognition and sleep, ruminative thinking and sleep, and metacognition and rumination in university students with a tendency towards generalized anxiety disorder. Mediation analysis showed that rumination partially mediated the effect of metacognition on sleep, with the mediating effect accounting for 51.1% of the total effect. There is a strong correlation between metacognition, rumination, and sleep in university students with a tendency towards generalized anxiety disorder, and both metacognition and rumination can predict sleep, while metacognition can affect sleep through the mediating effect of rumination.

9.
Technol Health Care ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38875060

RESUMO

BACKGROUND: The theory of Chinese medicine (TCM) constitution contributes to the optimisation of individualised healthcare programmes. However, at present, TCM constitution identification mainly relies on inefficient questionnaires with subjective bias. Efficient and accurate TCM constitution identification can play an important role in individualised medicine and healthcare. OBJECTIVE: Building an efficient model for identifying traditional Chinese medicine constitutions using objective tongue features and machine learning techniques. METHODS: The DS01-A device was applied to collect tongue images and extract features. We trained and evaluated five machine learning models: Support Vector Machine (SVM), Decision Tree (DT), Random Forest (RF), LightGBM (LGBM), and CatBoost (CB). Among these, we selected the model with the best performance as the base classifier for constructing our heterogeneous ensemble learning model. Using various performance metrics, including classification accuracy, precision, recall, F1 score, and area under curve (AUC), to comprehensively evaluate model performance. RESULTS: A total of 1149 tongue images were obtained and 45 features were extracted, forming dataset 1. RF, LGBM, and CB were selected as the base learners for the RLC-Stacking. On dataset 1, RLC-Stacking1 achieved an accuracy of 0.8122, outperforming individual classifiers. After feature selection, the classification accuracy of RLC-Stacking2 improved to 0.8287, an improvement of 0.00165 compared to RLC-Stacking1. RLC-Stacking2 achieved an accuracy exceeding 0.85 for identifying each TCM constitution type, indicating excellent identification performance. CONCLUSION: The study provides a reliable method for the accurate and rapid identification of TCM constitutions and can assist clinicians in tailoring individualized medical treatments based on personal constitution types and guide daily health care. The information extracted from tongue images serves as an effective marker for objective TCM constitution identification.

10.
Cell Commun Signal ; 22(1): 315, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849890

RESUMO

BACKGROUND: Aberrant inflammatory responses drive the initiation and progression of various diseases, and hyperactivation of NLRP3 inflammasome is a key pathogenetic mechanism. Pharmacological inhibitors of NLRP3 represent a potential therapy for treating these diseases but are not yet clinically available. The natural product butein has excellent anti-inflammatory activity, but its potential mechanisms remain to be investigated. In this study, we aimed to evaluate the ability of butein to block NLRP3 inflammasome activation and the ameliorative effects of butein on NLRP3-driven diseases. METHODS: Lipopolysaccharide (LPS)-primed bone-marrow-derived macrophages were pretreated with butein and various inflammasome stimuli. Intracellular potassium levels, ASC oligomerization and reactive oxygen species production were also detected to evaluate the regulatory mechanisms of butein. Moreover, mouse models of LPS-induced peritonitis, dextran sodium sulfate-induced colitis, and high-fat diet-induced non-alcoholic steatohepatitis were used to test whether butein has protective effects on these NLRP3-driven diseases. RESULTS: Butein blocks NLRP3 inflammasome activation in mouse macrophages by inhibiting ASC oligomerization, suppressing reactive oxygen species production, and upregulating the expression of the antioxidant pathway nuclear factor erythroid 2-related factor 2 (Nrf2). Importantly, in vivo experiments demonstrated that butein administration has a significant protective effect on the mouse models of LPS-induced peritonitis, dextran sodium sulfate-induced colitis, and high-fat diet-induced non-alcoholic steatohepatitis. CONCLUSION: Our study illustrates the connotation of homotherapy for heteropathy, i.e., the application of butein to broaden therapeutic approaches and treat multiple inflammatory diseases driven by NLRP3.


Assuntos
Chalconas , Inflamassomos , Lipopolissacarídeos , Macrófagos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR , Espécies Reativas de Oxigênio , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Chalconas/farmacologia , Chalconas/uso terapêutico , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Inflamassomos/metabolismo , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Masculino , Modelos Animais de Doenças , Colite/induzido quimicamente , Colite/patologia , Colite/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia
11.
Pharmaceutics ; 16(6)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38931853

RESUMO

Pharmaceutical excipient PEG400 is a common component of traditional Chinese medicine compound preparations. Studies have demonstrated that pharmaceutical excipients can directly or indirectly influence the disposition process of active drugs in vivo, thereby affecting the bioavailability of drugs. In order to reveal the pharmacokinetic effect of PEG400 on baicalin in hepatocytes and its mechanism, the present study first started with the effect of PEG400 on the metabolic disposition of baicalin at the hepatocyte level, and then the effect of PEG400 on the protein expression of baicalin-related transporters (BCRP, MRP2, and MRP3) was investigated by using western blot; the effect of MDCKII-BCRP, MDCKII-BCRP, MRP2, and MRP3 was investigated by using MDCKII-BCRP, MDCKII-MRP2, and MDCKII-MRP3 cell monolayer models, and membrane vesicles overexpressing specific transporter proteins (BCRP, MRP2, and MRP3), combined with the exocytosis of transporter-specific inhibitors, were used to study the effects of PEG400 on the transporters in order to explore the possible mechanisms of its action. The results demonstrated that PEG400 significantly influenced the concentration of baicalin in hepatocytes, and the AUC0-t of baicalin increased from 75.96 ± 2.57 µg·h/mL to 106.94 ± 2.22 µg·h/mL, 111.97 ± 3.98 µg·h/mL, and 130.42 ± 5.26 µg·h/mL (p ˂ 0.05). Furthermore, the efflux rate of baicalin was significantly reduced in the vesicular transport assay and the MDCKII cell model transport assay, which indicated that PEG400 had a significant inhibitory effect on the corresponding transporters. In conclusion, PEG400 can improve the bioavailability of baicalin to some extent by affecting the efflux transporters and thus the metabolic disposition of baicalin in the liver.

12.
J Agric Food Chem ; 72(25): 14264-14273, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38860833

RESUMO

Ergothioneine (EGT) is a naturally occurring derivative of histidine with diverse applications in the medicine, cosmetic, and food industries. Nevertheless, its sustainable biosynthesis faces hurdles due to the limited biosynthetic pathways, complex metabolic network of precursors, and high cost associated with fermentation. Herein, efforts were made to address these limitations first by reconstructing a novel EGT biosynthetic pathway from Methylobacterium aquaticum in Escherichia coli and optimizing it through plasmid copy number. Subsequently, the supply of precursor amino acids was promoted by engineering the global regulator, recruiting mutant resistant to feedback inhibition, and blocking competitive pathways. These metabolic modifications resulted in a significant improvement in EGT production, increasing from 35 to 130 mg/L, representing a remarkable increase of 271.4%. Furthermore, an economical medium was developed by replacing yeast extract with corn steep liquor, a byproduct of wet milling of corn. Finally, the production of EGT reached 595 mg/L with a productivity of 8.2 mg/L/h by exploiting fed-batch fermentation in a 10 L bioreactor. This study paves the way for exploring and modulating a de novo biosynthetic pathway for efficient and low-cost fermentative production of EGT.


Assuntos
Vias Biossintéticas , Ergotioneína , Escherichia coli , Fermentação , Engenharia Metabólica , Ergotioneína/biossíntese , Ergotioneína/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Reatores Biológicos
13.
Foods ; 13(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38890956

RESUMO

L-Arabinose isomerase (L-AI) has been commonly used as an efficient biocatalyst to produce D-tagatose via the isomerization of D-galactose. However, it remains a significant challenge to efficiently synthesize D-tagatose using the native (wild type) L-AI at an industrial scale. Hence, it is extremely urgent to redesign L-AI to improve its catalytic efficiency towards D-galactose, and herein a structure-based molecular modification of Lactobacillus plantarum CY6 L-AI (LpAI) was performed. Among the engineered LpAI, both F118M and F279I mutants showed an increased D-galactose isomerization activity. Particularly, the specific activity of double mutant F118M/F279I towards D-galactose was increased by 210.1% compared to that of the wild type LpAI (WT). Besides the catalytic activity, the substrate preference of F118M/F279I was also largely changed from L-arabinose to D-galactose. In the enzymatic production of D-tagatose, the yield and conversion ratio of F118M/F279I were increased by 81.2% and 79.6%, respectively, compared to that of WT. Furthermore, the D-tagatose production of whole cells expressing F118M/F279I displayed about 2-fold higher than that of WT cell. These results revealed that the designed site-directed mutagenesis is useful for improving the catalytic efficiency of LpAI towards D-galactose.

14.
J Org Chem ; 89(12): 8691-8705, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38856011

RESUMO

Organocatalyzed diastereo- and enantioselective [3 + 2] cycloaddition reactions of donor-acceptor (D-A) cyclopropanes with isatin-derived ketimines are presented. Different from well-developed Lewis acid activation protocols which promote the reactivity of D-A cyclopropanes through coordinating to the acceptor group, in this reaction, dicyanocyclopropylmethyl ketones can be activated through nucleophilic activation of the donor group by using dihydroquinine-derived squaramide as Brønsted base catalyst. The reaction affords functionalized spiro[oxindole-3,2'-pyrrolidines] with two nonadjacent tetra- and tri-substituted stereocenters in 83-99% yields, moderate to excellent diastereoselectivities (up to >20:1 diastereomeric ratio (dr)), and excellent enantioselectivities (up to >99% enantiomeric excess (ee)) under mild conditions.

15.
Int J Biol Macromol ; 274(Pt 1): 133260, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38901505

RESUMO

Hydroxypropyl starch-based composite system has high potential for many applications such as food packaging and biomedical fields. Here, how the incorporation of curdlan, a thermo-irreversible heating-set gel, tailors the processability, structure, and film performance of hydroxypropyl starch, a cooling-set gel, has been systematically investigated, aiming to achieve enhanced material properties favorable for edible packaging applications. Curdlan incorporation increased the shear-thinning behavior and viscosity of hydroxypropyl starch solution, which was also strongly affected by temperature. The miscibility and comparability between the two polymers with distinct gelation behaviors is a practical and interesting scientific topic. Scanning electron microscopy, dynamic mechanical analysis, and thermogravimetric analysis all indicated good compatibility between hydroxypropyl starch and curdlan. There was no observable phase boundary between the two materials, and all composite films showed only a single relaxation peak and only one polymer thermal decomposition peak. This resulted in improved structural density and overall performance. Compared with pure HPS film, the 7:3 HPS/CD film showed increases in tensile strength by 66.12 % and thermal decomposition temperature by 3 °C, and a reduction in water solubility by 11.72 %. This knowledge gained here may facilitate the development of edible films based on hydroxypropyl starch with satisfying film performance and processability.

16.
Angew Chem Int Ed Engl ; : e202407920, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38877853

RESUMO

Axially chiral biaryl δ-amino acids possess significantly different conformational properties and chiral environment from centrally chiral amino acids, therefore, have drawn considerable attention in the fields of synthetic and medicinal chemistry. Herein, a novel chiral phenanthroline-potassium catalyst has been developed by constructing a well-organized axially chiral ligand composed of one 1,10-phenanthroline unit and two axially chiral 1,1'-bi-2-naphthol (BINOL) units. In the presence of this catalyst, good to excellent yields and enantioselectivities (up to 99% yield, 98:2 er) have been achieved in the ring-opening alcoholytic dynamic kinetic resolution of a variety of biaryl lactams, thereby providing an efficient protocol for catalytic asymmetric synthesis of unnatural axially chiral biaryl δ-amino acid derivatives.

17.
Acta Pharm Sin B ; 14(6): 2716-2731, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38828148

RESUMO

Lipogenesis is often highly upregulated in breast cancer brain metastases to adapt to intracranial low lipid microenvironments. Lipase inhibitors hold therapeutic potential but their intra-tumoral distribution is often blocked by the blood‒tumor barrier (BTB). BTB activates its Wnt signaling to maintain barrier properties, e.g., Mfsd2a-mediated BTB low transcytosis. Here, we reported VCAM-1-targeting nano-wogonin (W@V-NPs) as an adjuvant of nano-orlistat (O@V-NPs) to intensify drug delivery and inhibit lipogenesis of brain metastases. W@V-NPs were proven to be able to inactivate BTB Wnt signaling, downregulate BTB Mfsd2a, accelerate BTB vesicular transport, and enhance tumor accumulation of O@V-NPs. With the ability to specifically kill cancer cells in a lipid-deprived environment with IC50 at 48 ng/mL, W@V-NPs plus O@V-NPs inhibited the progression of brain metastases with prolonged survival of model mice. The combination did not induce brain edema, cognitive impairment, and systemic toxicity in healthy mice. Targeting Wnt signaling could safely modulate the BTB to improve drug delivery and metabolic therapy against brain metastases.

18.
Chembiochem ; : e202400269, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38923255

RESUMO

The human malaria parasite Plasmodium falciparum (P. falciparum) continues to pose a significant public health challenge, leading to millions of fatalities globally. Halofuginone (HF) has shown a significant anti-P. falciparum effect, suggesting its potential as a therapeutic agent for malaria treatment. In this study, we synthesized a photoaffinity labeling probe of HF to identify its direct target in P. falciparum. Our results reveal that ubiquitin carboxyl-terminal hydrolase 3 (PfUCHL3) acts as a crucial target protein of HF, which modulates parasite growth in the intraerythrocytic cycle. In particular, we discovered that HF potentially forms hydrogen bonds with the Leu10, Glu11, and Arg217 sites of PfUCHL3, thereby inducing an allosteric effect by promoting the embedding of the helix 6' region on the protein surface. Furthermore, HF disrupts the expression of multiple functional proteins mediated by PfUCHL3, specifically those that play crucial roles in amino acid biosynthesis and metabolism in P. falciparum. Taken together, this study highlights PfUCHL3 as a previously undisclosed druggable target of HF, which contributes to the development of novel anti-malarial agents in the future.

19.
Ann Ital Chir ; 95(3): 338-346, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38918970

RESUMO

AIM: The aim of our study was to analyze risk factors for postoperative cerebral infarction in patients with glioma in our hospital, and to compare medical imaging techniques for early diagnosis of postoperative cerebral infarction. METHODS: A retrospective analysis was conducted on 178 patients (male: 78, female: 100) who underwent glioma surgery at our hospital between May 2015 and October 2023. They were divided into two groups based on the presence of postoperative cerebral infarction within 7 days: the cerebral infarction group (n = 85) and the non-cerebral infarction group (n = 93). Magnetic resonance imaging (MRI) was used to assess the location, distribution, and volume of the tumor before surgery. During the perioperative period, patient postoperative time, intraoperative blood loss, and other relevant data were documented. Computed tomography perfusion (CTP) and diffusion-weighted imaging (DWI) imaging techniques were employed to evaluate the occurrence, area, location, and shape of cerebral infarction. The imaging characteristics of postoperative cerebral infarction were noted. Apparent diffusion coefficient values, apparent diffusion coefficient (ADC) of whole-brain CTP parameters, cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and DWI parameters were measured. The sensitivity and specificity of CTP, DWI, and their combined diagnosis for postoperative cerebral infarction were compared, with consistency assessed using the Kappa value. RESULTS: This study found that 85 patients (47.8%) experienced postoperative cerebral infarction. Significant risk factors included tumor location in the temporal lobe, tumor volume ≥23.57 cm3, number of surgeries >1, World Health Organization (WHO) grade >3, and intraoperative blood loss >79.83 mL (p < 0.05). Imaging examinations revealed that CTP combined with DWI diagnosis detected cerebral infarctions in 84 patients, showing lower CBF and CBV, and higher TTP, and MTT in the infarct group (p < 0.05). The Kappa values for CTP, DWI, and the combined diagnosis were 0.762, 0.833, and 0.937, respectively (p < 0.001). CONCLUSIONS: The prevalence of cerebral infarction in patients with glioma is high and is affected by many factors. Timely imaging examination can detect and predict the occurrence of cerebral infarction in patients after surgery, which is of great significance for improving the prognosis of patients.


Assuntos
Neoplasias Encefálicas , Infarto Cerebral , Imagem de Difusão por Ressonância Magnética , Glioma , Complicações Pós-Operatórias , Humanos , Masculino , Estudos Retrospectivos , Feminino , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/etiologia , Infarto Cerebral/epidemiologia , Pessoa de Meia-Idade , Glioma/cirurgia , Glioma/diagnóstico por imagem , Glioma/complicações , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/diagnóstico por imagem , Prevalência , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Fatores de Risco , Idoso , Adulto , Tomografia Computadorizada por Raios X , Sensibilidade e Especificidade
20.
Chemosphere ; 359: 142324, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38740339

RESUMO

Seawater warming, ocean acidification and chemical pollution are the main threats to coral growth and even survival. The legacy persistent organic contaminants (POCs), such as polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), and the emerging contaminants, including polybrominated diphenyl ethers (PBDEs), dechlorane plus (DPs) and novel brominated flame retardants (NBFRs) were studied in corals from Luhuitou fringing reef in Sanya Bay and Yongle atoll in Xisha Islands, the South China Sea (SCS). Total average concentrations of ∑16PAHs, ∑23OCPs, ∑34PCBs, ∑8PBDEs, ∑2DPs and ∑5NBFRs in 20 coral species (43 samples) from the SCS were 40.7 ± 34.6, 5.20 ± 5.10, 0.197 ± 0.159, 3.30 ± 3.70, 0.041 ± 0.042 and 36.4 ± 112 ng g-1 dw, respectively. PAHs and NBFRs were the most abundant compounds and they are likely to be dangerous pollutants for future coral growth. Compared to those found in other coral reef regions, these pollutants concentrations in corals were at low to median levels. Except for PBDEs, POCs in massive Porites were significantly higher than those in branch Acropora and Pocillopora (p < 0.01), as large, closely packed corals may be beneficial for retaining more pollutant. The current study contributes valuable data on POCs, particularly for halogenated flame retardants (HFRs, including PBDEs, DPs and NBFRs), in corals from the SCS, and will improve our knowledge of the occurrence and fate of these pollutants in coral reef ecosystems.


Assuntos
Antozoários , Monitoramento Ambiental , Retardadores de Chama , Éteres Difenil Halogenados , Hidrocarbonetos Clorados , Poluentes Orgânicos Persistentes , Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos , Água do Mar , Poluentes Químicos da Água , Animais , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , China , Éteres Difenil Halogenados/análise , Retardadores de Chama/análise , Água do Mar/química , Bifenilos Policlorados/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Recifes de Corais , Oceanos e Mares
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