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1.
Schizophrenia (Heidelb) ; 10(1): 41, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580688

RESUMO

The aim of this study is to compare ecologically-valid measure (the Cambridge Prospective Memory Test, CAMPROMPT) and laboratory measure (eye-tracking paradigm) in assessing prospective memory (PM) in individuals with schizophrenia spectrum disorders (SSDs). In addition, eye-tracking indices are used to examine the relationship between PM and other cognitive domains in SSDs patients. Initially, the study sample was formed by 32 SSDs patients and 32 healthy control subjects (HCs) who were matched in sociodemographic profile and the performance on CAMPROMPT. An eye-tracking paradigm was employed to examine the differences in PM accuracy and key cognitive processes (e.g., cue monitoring) between the two groups. Additional 31 patients were then recruited to investigate the relationship between PM cue monitoring, other cognitive functions, and the severity of clinical symptoms within the SSDs group. The monitoring of PM cue was reflected in total fixation time and total fixation counts for distractor words. Cognitive functions were assessed using the Chinese version of the MATRICS Consensus Cognitive Battery (MCCB). The Positive and Negative Syndrome Scale (PANSS) was applied to assess psychopathology. SSDs patients exhibited fewer total fixation counts for distractor words and lower PM accuracy compared to HCs, even though they were priori matched on CAMPROMPT. Correlation analysis within the SSDs group (63 cases) indicated a negative correlation between PM accuracy and PANSS total score, and a positive correlation with working memory and attention/vigilance. Regression analysis within the SSDs group revealed that higher visual learning and lower PANSS total scores independently predicted more total fixation counts on distractor words. Impairment in cue monitoring is a critical factor in the PM deficits in SSDs. The eye-tracking laboratory paradigm has advantages over the ecologically-valid measurement in identifying the failure of cue detection, making it a more sensitive tool for PM deficits in patients with SSDs.

2.
Int J Rehabil Res ; 47(2): 129-134, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38587088

RESUMO

This study aimed to translate and validate the traditional Chinese version of the Community Integration Questionnaire-Revised (TC-CIQ-R) in patients with traumatic brain injury (TBI). We included participants aged ≥20 years and diagnosed as having TBI for ≥6 months from neurosurgical clinics. The 18-item TC-CIQ-R, Participation Measure - 3 Domains, 4 Dimensions (PM-3D4D), Extended Glasgow Outcome Scale (GOSE), and Taiwanese Quality of Life After Brain Injury (TQOLIBRI) were completed. The sample included 180 TBI survivors (54% male, mean age 47 years) of whom 87% sustained a mild TBI. Exploratory factor analysis extracted four factors - home integration, social integration, productivity, and electronic social networking - which explained 63.03% of the variation, after discarding the tenth item with a factor loading of 0.25. For criterion-related validity, the TC-CIQ-R was significantly correlated with the PM-3D4D; convergent validity was exhibited by demonstrating the associations between the TC-CIQ-R and TQOLIBRI. Known-group validity testing revealed significant differences in the subdomain and total scores of the TC-CIQ-R between participants with a mean GOSE score of ≤6 and >7 (all P  < 0.001). The TC-CIQ-R exhibited acceptable Cronbach's α values (0.68-0.88). We suggest the 17-item TC-CIQ-R as a valid tool for rehabilitation professionals, useful for both clinical practice and research in assessing community integration levels following TBI.


Assuntos
Lesões Encefálicas Traumáticas , Integração Comunitária , Psicometria , Qualidade de Vida , Humanos , Masculino , Feminino , Lesões Encefálicas Traumáticas/reabilitação , Lesões Encefálicas Traumáticas/psicologia , Pessoa de Meia-Idade , Adulto , Inquéritos e Questionários , Análise Fatorial , Taiwan , Reprodutibilidade dos Testes , Escala de Resultado de Glasgow , Sobreviventes/psicologia , Traduções , Integração Social , Idoso
3.
J Psychosom Res ; 181: 111666, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38657565

RESUMO

OBJECTIVE: Patients often experience pain and psychological distress when undergoing elective surgeries. Mindfulness-based interventions have been proposed as potential strategies to address these challenges. This meta-analysis aims to evaluate the efficacy of preoperative mindfulness-based interventions on several outcomes for patients undergoing elective surgery, including preoperative anxiety/depression, postoperative anxiety/depression, postoperative pain, and quality of life (QOL). METHODS: This meta-analysis encompassed randomized controlled trials published in the database PubMed, Cochrane, and Embase to August 2023. Mindfulness-based interventions were compared to control groups, who received treatment as usual (TAU). The RevMan software was employed to assess each outcome by using standardized mean difference based on patient-reported data. Subgroup analyses were further performed according to different categories of surgical types. RESULTS: Eight RCTs with a total of 685 patients were identified. This meta-analysis demonstrated significant difference in preoperative anxiety (SMD:-0.36, 95% CI: -0.62 to -0.11, p = .006) and postoperative pain immediately (SMD:-0.65,95% CI: -1.09 to -0.20, p = .004), 2-3 days (SMD:-0.40, 95% CI:-0.78 to -0.02, p = .04),at 14 days (SMD:-0.48,95% CI: -0.85 to -0.12, p = .009) and 28 days (SMD:-0.89,95% CI: -1.55 to -0.23, p = .008) postoperatively. However, there were no differences between postoperative anxiety, preoperative/postoperative depression, and QOL. CONCLUSION: Our findings suggest preoperative mindfulness-based interventions can effectively manage preoperative anxiety and postoperative pain in patients scheduled for elective surgery. Further research is warranted to explore the different timing and types of mindfulness-based intervention.

4.
Mitochondrial DNA B Resour ; 9(4): 423-427, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38586511

RESUMO

Lagochilus ilicifolius Bunge ex Bentham, Labiat. Gen is a perennial herb with much-branched stems native to Nei Mongol, Ningxia, Gansu, N Shaanxi. It can be used clinically as a hemostatic agent. The chloroplast genome length is 151,466 bp. It contained two inverted repeat regions of 25,660 bp each, a large single-copy region of length 82,504 bp, and a small single-copy region of length 17,642 bp. Also, the GC content is 38.6%. There were 133 genes annotated, including 88 known protein-coding genes, 37 tRNAs, and eight rRNAs. The phylogenetic tree was constructed using Bayesian method for plastome data of 29 species. The entire chloroplast genome of L. ilicifolius within the Lamiaceae is the first to reveal genetic taxonomy at the molecular level, and the new phylogenetic tree data can be used for future evolutionary studies.

5.
Proc Natl Acad Sci U S A ; 121(11): e2318320121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38457518

RESUMO

Coordinated carbon and nitrogen metabolism is crucial for bacteria living in the fluctuating environments. Intracellular carbon and nitrogen homeostasis is maintained by a sophisticated network, in which the widespread signaling protein PII acts as a major regulatory hub. In cyanobacteria, PII was proposed to regulate the nitrate uptake by an ABC (ATP-binding cassette)-type nitrate transporter NrtABCD, in which the nucleotide-binding domain of NrtC is fused with a C-terminal regulatory domain (CRD). Here, we solved three cryoelectron microscopy structures of NrtBCD, bound to nitrate, ATP, and PII, respectively. Structural and biochemical analyses enable us to identify the key residues that form a hydrophobic and a hydrophilic cavity along the substrate translocation channel. The core structure of PII, but not the canonical T-loop, binds to NrtC and stabilizes the CRD, making it visible in the complex structure, narrows the substrate translocation channel in NrtB, and ultimately locks NrtBCD at an inhibited inward-facing conformation. Based on these results and previous reports, we propose a putative transport cycle driven by NrtABCD, which is allosterically inhibited by PII in response to the cellular level of 2-oxoglutarate. Our findings provide a distinct regulatory mechanism of ABC transporter via asymmetrically binding to a signaling protein.


Assuntos
Cianobactérias , Transportadores de Nitrato , Nitratos/metabolismo , Proteínas de Bactérias/metabolismo , Regulação Alostérica , Microscopia Crioeletrônica , Cianobactérias/metabolismo , Trifosfato de Adenosina/metabolismo , Nitrogênio/metabolismo , Carbono/metabolismo , Proteínas PII Reguladoras de Nitrogênio/genética , Proteínas PII Reguladoras de Nitrogênio/metabolismo
6.
Front Psychiatry ; 15: 1343188, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505800

RESUMO

Objective: The aim of this study was to investigate the impact of early life adversity on cognitive function in patients with schizophrenia, with a focus on social cognition (SC). Methods: Two groups of patients with schizophrenia were recruited and matched on sociodemographic and clinical characteristics. One group consisted of 32 patients with a history of childhood trauma (SCZ-ct), and the other group consisted of 30 patients without a history of childhood trauma (SCZ-nct). In addition, 39 healthy controls without a history of childhood trauma (HC-nct) were also recruited. The intelligence of the three groups was assessed using the Wechsler Abbreviated Scale of Intelligence (WAIS-RC) short version. The cognitive function evaluation was conducted using the MATRICS Consensus Cognitive Battery (MCCB), and early life adversity was measured using the Childhood Trauma Questionnaire-Short Form (CTQ) and Bullying Scale for Adults (BSA). Results: Patients with schizophrenia endosed significantly higher scores on the CTQ (F=67.61, p<0.001) and BSA (F=9.84, p<0.001) compared to the HC-nct. Analysis of covariance (ANCOVA) and post-hoc analyses revealed that SCZ-ct (F=11.20, p<0.001) exhibited the most pronounced cognitive impairment among the three groups, as indicated in MCCB total scores and in the domain score of SC. CTQ exhibited a negative correlation with MCCB (r=-0.405, p< 0.001); SC was negatively correlated with physical abuse (PA) of CTQ (r=-0.271, p=0.030) and emotional abuse (EA) of BSA (r=-0.265, p=0.034) in the whole patient sample. Higher SC performance was significantly predicted by CT_total (Beta =-0.582, p<0.001, 95% CI -0.96-0.46), and years of education (Beta=0.260, p =0.014, 95% CI 0.20-1.75) in schizophrenia. Conclusions: Besides familial trauma, schizophrenia patients appear to have a higher likelihood of experiencing bullying in their early life. These experiences seem to contribute significantly to their severe impairments in SC.

7.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(2): 151-157, 2024 Feb 15.
Artigo em Chinês | MEDLINE | ID: mdl-38436312

RESUMO

OBJECTIVES: To investigate the differences in visual perception between children with autism spectrum disorder (ASD) and typically developing (TD) children when watching different intention videos, and to explore the feasibility of machine learning algorithms in objectively distinguishing between ASD children and TD children. METHODS: A total of 58 children with ASD and 50 TD children were enrolled and were asked to watch the videos containing joint intention and non-joint intention, and the gaze duration and frequency in different areas of interest were used as original indicators to construct classifier-based models. The models were evaluated in terms of the indicators such as accuracy, sensitivity, and specificity. RESULTS: When using eight common classifiers, including support vector machine, linear discriminant analysis, decision tree, random forest, and K-nearest neighbors (with K values of 1, 3, 5, and 7), based on the original feature indicators, the highest classification accuracy achieved was 81.90%. A feature reconstruction approach with a decision tree classifier was used to further improve the accuracy of classification, and then the model showed the accuracy of 91.43%, the specificity of 89.80%, and the sensitivity of 92.86%, with an area under the receiver operating characteristic curve of 0.909 (P<0.001). CONCLUSIONS: The machine learning model based on eye-tracking data can accurately distinguish ASD children from TD children, which provides a scientific basis for developing rapid and objective ASD screening tools.


Assuntos
Transtorno do Espectro Autista , Criança , Humanos , Transtorno do Espectro Autista/diagnóstico , Tecnologia de Rastreamento Ocular , Intenção , Algoritmos , Aprendizado de Máquina
8.
Chem Biodivers ; : e202400210, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433548

RESUMO

Currently, natural products are one of the priceless options for finding novel chemical pharmaceutical entities. Ellipticine is a naturally occurring alkaloid isolated from the leaves of Ochrosia elliptica Labill. Ellipticine and its derivatives are characterized by multiple biological activities. The purpose of this review was to provide a critical and systematic assessment of ellipticine and its derivatives as bioactive molecules over the last 60 years. Publications focused mainly on the total synthesis of alkaloids of this type without any evaluation of bioactivity have been excluded. We have reviewed papers dealing with the synthesis, bioactivity evaluation and mechanism of action of ellipticine and its derivatives. It was found that ellipticine and its derivatives showed cytotoxicity, antimicrobial ability, and anti-inflammatory activity, among which cytotoxicity toward cancer cell lines was the most investigated aspect. The inhibition of DNA topoisomerase II was the most relevant mechanism for cytotoxicity. The PI3K/AKT pathway, p53 pathway, and MAPK pathway were also closely related to the antiproliferative ability of these compounds. In addition, the structure-activity relationship was deduced, and future prospects were outlined. We are confident that these findings will lay a scientific foundation for ellipticine-based drug development, especially for anticancer agents.

9.
Microb Cell Fact ; 23(1): 87, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515152

RESUMO

BACKGROUND: Natural tetramates are a family of hybrid polyketides bearing tetramic acid (pyrrolidine-2,4-dione) moiety exhibiting a broad range of bioactivities. Biosynthesis of tetramates in microorganisms is normally directed by hybrid polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) machineries, which form the tetramic acid ring by recruiting trans- or cis-acting thioesterase-like Dieckmann cyclase in bacteria. There are a group of tetramates with unique skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, which remain to be investigated for their biosynthetic logics. RESULTS: Herein, the tetramate type compounds bripiodionen (BPD) and its new analog, featuring the rare skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, were discovered from the sponge symbiotic bacterial Streptomyces reniochalinae LHW50302. Gene deletion and mutant complementation revealed the production of BPDs being correlated with a PKS-NRPS biosynthetic gene cluster (BGC), in which a Dieckmann cyclase gene bpdE was identified by sit-directed mutations. According to bioinformatic analysis, the tetramic acid moiety of BPDs should be formed on an atypical NRPS module constituted by two discrete proteins, including the C (condensation)-A (adenylation)-T (thiolation) domains of BpdC and the A-T domains of BpdD. Further site-directed mutagenetic analysis confirmed the natural silence of the A domain in BpdC and the functional necessities of the two T domains, therefore suggesting that an unusual aminoacyl transthiolation should occur between the T domains of two NRPS subunits. Additionally, characterization of a LuxR type regulator gene led to seven- to eight-fold increasement of BPDs production. The study presents the first biosynthesis case of the natural molecule with 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione skeleton. Genomic mining using BpdD as probe reveals that the aminoacyl transthiolation between separate NRPS subunits should occur in a certain population of NRPSs in nature.


Assuntos
Vias Biossintéticas , Policetídeo Sintases , Pirrolidinonas , Policetídeo Sintases/metabolismo , Bactérias/metabolismo , Piranos/metabolismo , Esqueleto/metabolismo , Peptídeo Sintases/genética
10.
Biomed Pharmacother ; 173: 116406, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460366

RESUMO

Sanguinarine is a quaternary ammonium benzophenanthine alkaloid found in traditional herbs such as Chelidonium, Corydalis, Sanguinarum, and Borovula. It has been proven to possess broad-spectrum biological activities, such as antitumor, anti-inflammatory, antiosteoporosis, neuroprotective, and antipathogenic microorganism activities. In this paper, recent progress on the biological activity and mechanism of action of sanguinarine and its derivatives over the past ten years is reviewed. The results showed that the biological activities of hematarginine and its derivatives are related mainly to the JAK/STAT, PI3K/Akt/mTOR, NF-κB, TGF-ß, MAPK and Wnt/ß-catenin signaling pathways. The limitations of using sanguinarine in clinical application are also discussed, and the research prospects of this subject are outlined. In general, sanguinarine, a natural medicine, has many pharmacological effects, but its toxicity and safety in clinical application still need to be further studied. This review provides useful information for the development of sanguinarine-based bioactive agents.


Assuntos
Alcaloides , Fosfatidilinositol 3-Quinases , Fosfatidilinositol 3-Quinases/metabolismo , Benzofenantridinas/farmacologia , Alcaloides/metabolismo , Isoquinolinas/farmacologia
11.
Angew Chem Int Ed Engl ; 63(19): e202316717, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38477147

RESUMO

The electrolytes for lithium metal batteries (LMBs) are plagued by a low Li+ transference number (T+) of conventional lithium salts and inability to form a stable solid electrolyte interphase (SEI). Here, we synthesized a self-folded lithium salt, lithium 2-[2-(2-methoxy ethoxy)ethoxy]ethanesulfonyl(trifluoromethanesulfonyl) imide (LiETFSI), and comparatively studied with its structure analogue, lithium 1,1,1-trifluoro-N-[2-[2-(2-methoxyethoxy)ethoxy)]ethyl]methanesulfonamide (LiFEA). The special anion chemistry imparts the following new characteristics: i) In both LiFEA and LiETFSI, the ethylene oxide moiety efficiently captures Li+, resulting in a self-folded structure and high T+ around 0.8. ii) For LiFEA, a Li-N bond (2.069 Å) is revealed by single crystal X-ray diffraction, indicating that the FEA anion possesses a high donor number (DN) and thus an intensive interphase "self-cleaning" function for an ultra-thin and compact SEI. iii) Starting from LiFEA, an electron-withdrawing sulfone group is introduced near the N atom. The distance of Li-N is tuned from 2.069 Šin LiFEA to 4.367 Šin LiETFSI. This alteration enhances ionic separation, achieves a more balanced DN, and tunes the self-cleaning intensity for a reinforced SEI. Consequently, the fast charging/discharging capability of LMBs is progressively improved. This rationally tuned anion chemistry reshapes the interactions among Li+, anions, and solvents, presenting new prospects for advanced LMBs.

12.
Front Surg ; 11: 1371641, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38425375

RESUMO

[This corrects the article DOI: 10.3389/fsurg.2022.939591.].

13.
Schizophr Res Cogn ; 36: 100304, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38444400

RESUMO

The hematopoietically-expressed homeobox gene (HHEX) played a critical role in regulating the immune system that the abnormality of which was involved in the psychopathology and cognitive deficits of psychiatric disorders. The aim of this study was to investigate the effect of HHEX rs1111875 polymorphism on the susceptibility and cognitive deficits of first-episode schizophrenic patients (FSP). We assessed cognitive function in 239 first-episode patients meeting DSM-IV for schizophrenia, and 368 healthy controls using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). The HHEX rs1111875 polymorphism was genotyped. Our results showed that the allelic and genotypic frequencies of HHEX rs1111875 polymorphism didn't differ between FSP and healthy controls (both p > 0.05) after adjusting for sex and age. Cognitive test scores in FSP were significantly lower than those in healthy controls on all scales (all p < 0.001) except for the visuospatial/constructional score (p > 0.05) after adjusting for covariates. There was a significant genotype (p < 0.05) rather than genotype × diagnosis (p > 0.05) effect on the delayed memory score after adjusting for covariates. The HHEX rs1111875 polymorphism was significantly associated with the delayed memory score in FSP (p < 0.05), but not in healthy controls (p > 0.05) after adjusting for covariates. Our findings supported that the HHEX rs1111875 polymorphism did not contribute to the susceptibility to FSP. However, this polymorphism might influence the delayed memory in FSP. Moreover, FSP had poorer cognitive function than healthy controls except for the visuospatial/constructional domain.

14.
Heliyon ; 10(5): e26861, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439880

RESUMO

Objective: The aim of this study was to systematically review the clinical efficacy and safety of standardized Ginkgo biloba extract (GBE) in the adjuvant treatment of intracerebral hemorrhage (ICH). Methods: Relevant RCTs on GBE as adjuvant therapy for ICH were searched in seven Chinese and English databases. Data extraction of the included literature was performed after duplicate checking and screening, and Stata 15.1 software was applied for data analysis. Results: With a total of 19 RCTs, the meta-analysis results showed that: Compared with conventional treatment alone, GBE combined with conventional treatment had a higher effective rate; NIHSS score and CSS score were lower; The residual hematoma was less. The volume of cerebral edema was smaller. ADL score was higher. MoCA score was higher. The serum levels of hs-CRP, TNF-α and IL-6 were lower; No significant difference was observed in the incidence of adverse reactions between conventional treatment alone and GBE combined with conventional treatment. Conclusion: This study suggests that GBE as adjuvant therapy for ICH has better efficacy and is relatively safe compared with conventional treatment alone. However, due to the quality and quantity of included studies, further validation by more methodologically rigorous and multi-center studies with larger sample sizes is needed.

15.
Drug Dev Res ; 85(2): e22165, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38400652

RESUMO

Isocryptomerin (ISO) is a flavonoid isolated from the natural medicine Selaginellae Herba, which has various pharmacological activities. This study investigated the antitumor effect and underlying molecular mechanism of ISO on hepatocellular carcinoma (HCC) HepG2 cells. The cell viability assay revealed that ISO has a considerable killing effect on HCC cell lines. The apoptosis assay showed that ISO induced mitochondria-dependent apoptosis through the Bad/cyto-c/cleaved (cle)-caspase-3/cleaved (cle)-PARP pathway. The network pharmacological analysis found 13 key target genes, and epidermal growth factor receptor (EGFR), AKT, mitogen-activated protein kinase (MAPK), and reactive oxygen species (ROS) signaling pathways were strongly associated with ISO against HCC. Further verification of the results showed that ISO induced apoptosis by increasing p-p38 and p-JNK expression and decreasing p-EGFR, p-SRC, p-ERK, and p-STAT3 expression. Furthermore, ISO induced G0/G1 phase arrest by downregulating p-AKT, Cyclin D, and CDK 4 expression and upregulating p21 and p27 expression in HepG2 cells. Moreover, ISO inhibited HepG2 cell migration by decreasing p-GSK-3ß, ß-catenin, and N-cadherin expression and increasing E-cadherin expression. Additionally, ISO promoted ROS accumulation in HepG2 cells, and ISO-induced apoptosis, arrest cell cycle, and inhibition of migration were reversed by an ROS scavenger, N-acetyl- l-cysteine. Overall, ISO induced cell apoptosis and cell cycle arrest and inhibited cell migration by ROS-mediated EGFR, AKT, and MAPK signaling pathways in HepG2 cells.


Assuntos
Carcinoma Hepatocelular , Flavonas , Neoplasias Hepáticas , Humanos , Células Hep G2 , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Glicogênio Sintase Quinase 3 beta , Farmacologia em Rede , Receptores ErbB
16.
J Am Chem Soc ; 146(12): 8206-8215, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38412246

RESUMO

Spin-crossover (SCO) materials exhibit remarkable potential as bistable switches in molecular devices. However, the spin transition temperatures (Tc) of known compounds are unable to cover the entire ambient temperature spectrum, largely limiting their practical utility. This study reports an exemplary two-dimensional SCO solid solution system, [FeIII(H0.5LCl)2-2x(H0.5LF)2x]·H2O (H0.5LX = 5-X-2-hydroxybenzylidene-hydrazinecarbothioamide, X = F or Cl, x = 0 to 1), in which the adjacent layers are adhered via hydrogen bonding. Notably, the Tc of this system can be fine-tuned across 90 K (227-316 K) in a linear manner by modulating the fraction x of the LF ligand. Elevating x results in strengthened hydrogen bonding between adjacent layers, which leads to enhanced intermolecular interactions between adjacent SCO molecules. Single-crystal diffraction analysis and periodic density functional theory calculations revealed that such a special kind of alteration in interlayer interactions strengthens the FeIIIN2O2S2 ligand field and corresponding SCO energy barrier, consequently resulting in increased Tc. This work provides a new pathway for tuning the Tc of SCO materials through delicate manipulation of molecular interactions, which could expand the application of bistable molecular solids to a much wider temperature regime.

17.
Phytochemistry ; 220: 114017, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342290

RESUMO

Marine sponges are well known as prolific producers of structurally diverse molecules with valuable pharmacological potential. As part of our ongoing program to discover bioactive compounds from marine sponges collected from the Xisha Islands in the South China Sea, a chemical study on the specimens of Hippospongia lachne was conducted. As a result, eight undescribed compounds, including four zwitterionic alkylpyridinium salts, hippospondines A-D (1-4), and four 3-alkylpyridine alkaloids, hippospondines E (5), F (6), and (±)-hippospondine G (7), were isolated from the marine sponge H. lachne, together with one known 3-alkylpyridine alkaloid (8). The undescribed structures were elucidated by HRESIMS, NMR, DP4+ and CP3 probability analysis, and the Snatzke's method. Hippospondines A-D (1-4) represent the rare example of inner salt type alkylpyridinium alkaloid with a farnesyl moiety. Compounds 1-3 and 8 were subjected to cytotoxic and lymphocyte proliferation assays. Compound 3 exhibited a weak promotion effect on the ConA-induced T lymphocyte proliferation.


Assuntos
Alcaloides , Antineoplásicos , Poríferos , Animais , Espectroscopia de Ressonância Magnética , Antineoplásicos/química , Alcaloides/química , China , Estrutura Molecular
18.
Nat Commun ; 15(1): 1061, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316776

RESUMO

Bilirubin is mainly generated from the breakdown of heme when red blood cells reach the end of their lifespan. Accumulation of bilirubin in human body usually leads to various disorders, including jaundice and liver disease. Bilirubin is conjugated in hepatocytes and excreted to bile duct via the ATP-binding cassette transporter ABCC2, dysfunction of which would lead to Dubin-Johnson syndrome. Here we determine the structures of ABCC2 in the apo, substrate-bound and ATP/ADP-bound forms using the cryo-electron microscopy, exhibiting a full transporter with a regulatory (R) domain inserted between the two half modules. Combined with substrate-stimulated ATPase and transport activity assays, structural analysis enables us to figure out transport cycle of ABCC2 with the R domain adopting various conformations. At the rest state, the R domain binding to the translocation cavity functions as an affinity filter that allows the substrates of high affinity to be transported in priority. Upon substrate binding, the R domain is expelled from the cavity and docks to the lateral of transmembrane domain following ATP hydrolysis. Our findings provide structural insights into a transport mechanism of ABC transporters finely tuned by the R domain.


Assuntos
Bilirrubina , Proteína 2 Associada à Farmacorresistência Múltipla , Humanos , Trifosfato de Adenosina/metabolismo , Microscopia Crioeletrônica , Proteína 2 Associada à Farmacorresistência Múltipla/genética , Proteína 2 Associada à Farmacorresistência Múltipla/metabolismo
19.
Acta Pharm Sin B ; 14(2): 533-578, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38322348

RESUMO

Epigenetic pathways play a critical role in the initiation, progression, and metastasis of cancer. Over the past few decades, significant progress has been made in the development of targeted epigenetic modulators (e.g., inhibitors). However, epigenetic inhibitors have faced multiple challenges, including limited clinical efficacy, toxicities, lack of subtype selectivity, and drug resistance. As a result, the design of new epigenetic modulators (e.g., degraders) such as PROTACs, molecular glue, and hydrophobic tagging (HyT) degraders has garnered significant attention from both academia and pharmaceutical industry, and numerous epigenetic degraders have been discovered in the past decade. In this review, we aim to provide an in-depth illustration of new degrading strategies (2017-2023) targeting epigenetic proteins for cancer therapy, focusing on the rational design, pharmacodynamics, pharmacokinetics, clinical status, and crystal structure information of these degraders. Importantly, we also provide deep insights into the potential challenges and corresponding remedies of this approach to drug design and development. Overall, we hope this review will offer a better mechanistic understanding and serve as a useful guide for the development of emerging epigenetic-targeting degraders.

20.
Redox Rep ; 29(1): 2313366, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38318818

RESUMO

Jaceosidin (JAC) is a natural flavonoid with anti-oxidant and other pharmacological activities; however, its anti-cancer mechanism remains unclear. We investigated the mechanism of action of JAC in gastric cancer cells. Cytotoxicity and apoptosis assays showed that JAC effectively killed multiple gastric cancer cells and induced apoptosis in human gastric adenocarcinoma AGS cells via the mitochondrial pathway. Network pharmacological analysis suggested that its activity was linked to reactive oxygen species (ROS), AKT, and MAPK signaling pathways. Furthermore, JAC accumulated ROS to up-regulate p-JNK, p-p38, and IκB-α protein expressions and down-regulate the p-ERK, p-STAT3, and NF-κB protein expressions. Cell cycle assay results showed that JAC accumulated ROS to up-regulate p21 and p27 protein expressions and down-regulate p-AKT, CDK2, CDK4, CDK6, Cyclin D1, and Cyclin E protein expressions to induce G0/G1 phase arrest. Cell migration assay results showed JAC accumulated ROS to down-regulate Wnt-3a, p-GSK-3ß, N-cadherin, and ß-catenin protein expressions and up-regulate E-cadherin protein expression to inhibit migration. Furthermore, N-acetyl cysteine pre-treatment prevented the change of these protein expressions. In summary, JAC induced apoptosis and G0/G1 phase arrest and inhibited migration through ROS-mediated signaling pathways in AGS cells.


Assuntos
Neoplasias Gástricas , Humanos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Flavonoides/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
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