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1.
Med Phys ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38994881

RESUMO

BACKGROUND: Cardiac stereotactic body radiotherapy (CSBRT) is an emerging and promising noninvasive technique for treating refractory arrhythmias utilizing highly precise, single or limited-fraction high-dose irradiations. This method promises to revolutionize the treatment of cardiac conditions by delivering targeted therapy with minimal exposure to surrounding healthy tissues. However, the dynamic nature of cardiorespiratory motion poses significant challenges to the precise delivery of dose in CSBRT, introducing potential variabilities that can impact treatment efficacy. The complexities of the influence of cardiorespiratory motion on dose distribution are compounded by interplay and blurring effects, introducing additional layers of dose uncertainty. These effects, critical to the understanding and improvement of the accuracy of CSBRT, remain unexplored, presenting a gap in current clinical literature. PURPOSE: To investigate the cardiorespiratory motion characteristics in arrhythmia patients and the dosimetric impact of interplay and blurring effects induced by cardiorespiratory motion on CSBRT plan quality. METHODS: The position and volume variations in the substrate target and cardiac substructures were evaluated in 12 arrhythmia patients using displacement maximum (DMX) and volume metrics. Moreover, a four-dimensional (4D) dose reconstruction approach was employed to examine the dose uncertainty of the cardiorespiratory motion. RESULTS: Cardiac pulsation induced lower DMX than respiratory motion but increased the coefficient of variation and relative range in cardiac substructure volumes. The mean DMX of the substrate target was 0.52 cm (range: 0.26-0.80 cm) for cardiac pulsation and 0.82 cm (range: 0.32-2.05 cm) for respiratory motion. The mean DMX of the cardiac structure ranged from 0.15 to 1.56 cm during cardiac pulsation and from 0.35 to 1.89 cm during respiratory motion. Cardiac pulsation resulted in an average deviation of -0.73% (range: -4.01%-4.47%) in V25 between the 3D and 4D doses. The mean deviations in the homogeneity index (HI) and gradient index (GI) were 1.70% (range: -3.10%-4.36%) and 0.03 (range: -0.14-0.11), respectively. For cardiac substructures, the deviations in D50 due to cardiac pulsation ranged from -1.88% to 1.44%, whereas the deviations in Dmax ranged from -2.96% to 0.88% of the prescription dose. By contrast, the respiratory motion led to a mean deviation of -1.50% (range: -10.73%-4.23%) in V25. The mean deviations in HI and GI due to respiratory motion were 4.43% (range: -3.89%-13.98%) and 0.18 (range: -0.01-0.47) (p < 0.05), respectively. Furthermore, the deviations in D50 and Dmax in cardiac substructures for the respiratory motion ranged from -0.28% to 4.24% and -4.12% to 1.16%, respectively. CONCLUSIONS: Cardiorespiratory motion characteristics vary among patients, with the respiratory motion being more significant. The intricate cardiorespiratory motion characteristics and CSBRT plan complexity can induce substantial dose uncertainty. Therefore, assessing individual motion characteristics and 4D dose reconstruction techniques is critical for implementing CSBRT without compromising efficacy and safety.

2.
Neurosurg Focus ; 56(6): E18, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38823051

RESUMO

OBJECTIVE: This study aimed to investigate the differences in clinical features, diagnostic examination, treatment, and pathological results between adult-onset and pediatric-onset tethered cord syndrome (TCS). METHODS: The authors searched the PubMed, Embase, and Cochrane Library databases through January 2023 for reports on TCS, extracting information on clinical features, imaging data, treatment modalities, prognosis, and pathological research results. A total of 6135 cases from 246 articles were included in the analysis. This review was conducted in accordance with the 2020 PRISMA guidelines and registered on PROSPERO. RESULTS: The most common adult clinical manifestations were pain, urinary symptoms, and numbness; in children, they were urinary symptoms, skin lesions, bowel symptoms, and unspecific motor deficits. Surgical treatment was the primary approach for both adults and children, with a higher clinical improvement rate observed in adults. However, adults also had a higher rate of surgical complications than children. TCS pathological studies have not yet identified the differences between adults and children, and the pathogenesis of adult-onset TCS requires further investigation. CONCLUSIONS: Adult-onset and pediatric-onset TCS exhibit certain differences in clinical characteristics, diagnostic examinations, and treatments. However, significant differences have not been found in current pathological studies between adults and children. Systematic review registration no.: CRD42023479450 (www.crd.york.ac.uk/prospero).


Assuntos
Defeitos do Tubo Neural , Humanos , Defeitos do Tubo Neural/cirurgia , Defeitos do Tubo Neural/diagnóstico , Criança , Adulto , Idade de Início
3.
Hepatology ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38899975

RESUMO

BACKGROUND AND AIMS: Liver HCC is the second leading cause of cancer-related deaths worldwide. The heterogeneity of this malignancy is driven by a wide range of genetic alterations, leading to a lack of effective therapeutic options. In this study, we conducted a systematic multi-omics characterization of HCC to uncover its metabolic reprogramming signature. APPROACH AND RESULTS: Through a comprehensive analysis incorporating transcriptomic, metabolomic, and lipidomic investigations, we identified significant changes in metabolic pathways related to glucose flux, lipid oxidation and degradation, and de novo lipogenesis in HCC. The lipidomic analysis revealed abnormal alterations in glycerol-lipids, phosphatidylcholine, and sphingolipid derivatives. Machine-learning techniques identified a panel of genes associated with lipid metabolism as common biomarkers for HCC across different etiologies. Our findings suggest that targeting phosphatidylcholine with saturated fatty acids and long-chain sphingolipid biosynthesis pathways, particularly by inhibiting lysophosphatidylcholine acyltransferase 1 ( LPCAT1 ) and ceramide synthase 5 ( CERS5 ) as potential therapeutic strategies for HCC in vivo and in vitro. Notably, our data revealed an oncogenic role of CERS5 in promoting tumor progression through lipophagy. CONCLUSIONS: In conclusion, our study elucidates the metabolic reprogramming nature of lipid metabolism in HCC, identifies prognostic markers and therapeutic targets, and highlights potential metabolism-related targets for therapeutic intervention in HCC.

4.
Stress Biol ; 4(1): 29, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38861095

RESUMO

In eukaryotes, the nuclear membrane that encapsulates genomic DNA is composed of an inner nuclear membrane (INM), an outer nuclear membrane (ONM), and a perinuclear space. SUN proteins located in the INM and KASH proteins in the ONM form the SUN-KASH NM-bridge, which functions as the junction of the nucleocytoplasmic complex junction. Proteins containing the SUN domain showed the highest correlation with differentially accumulated proteins (DAPs) in the wheat response to fungal stress. To understand the characteristics of SUN and its associated proteins in wheat responding to pathogen stress, here we investigated and comprehensive analyzed SUN- and KASH-related proteins among the DAPs under fungi infection based on their conserved motifs. In total, four SUN proteins, one WPP domain-interacting protein (WIP), four WPP domain-interacting tail-anchored proteins (WIT), two WPP proteins and one Ran GTPase activating protein (RanGAP) were identified. Following transient expression of Nicotiana benthamiana, TaSUN2, TaRanGAP2, TaWIT1 and TaWIP1 were identified as nuclear membrane proteins, while TaWPP1 and TaWPP2 were expressed in both the nucleus and cell membrane. RT-qPCR analysis demonstrated that the transcription of TaSUN2, TaRanGAP2 and TaWPP1 were strongly upregulated in response to fungal infection. Furthermore, using the bimolecular fluorescence complementation, the luciferase complementation and a nuclear and split-ubiquitin-based membrane yeast two-hybrid systems, we substantiated the interaction between TaSUN2 and TaWIP1, as well as TaWIP1/WIT1 and TaWPP1/WPP2. Silencing of TaSUN2, TaRanGAP2 and TaWPP1 in wheat leaves promoted powdery mildew infection and hyphal growth, and reduced the expression of TaBRI1, TaBAK1 and Ta14-3-3, indicating that these NM proteins play a positive role in resistance to fungal stress. Our study reveals the characteristics of NM proteins and propose the preliminary construction of SUN-WIP-WPP-RanGAP complex in wheat, which represents a foundation for detail elucidating their functions in wheat in future.

5.
J Biomed Res ; : 1-23, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38808552

RESUMO

Ferroptosis is an iron-mediated regulatory cell death pattern characterized by oxidative damage. The molecular regulating mechanisms are related to iron metabolism, lipid peroxidation, and glutathione metabolism. Additionally, some immunological signaling pathways, such as the cyclic GMP-AMP synthase-stimulator ofinterferon genes axis, Janus kinase-signal transducer and activator of transcription 1 axis, and transforming growth factor beta 1-Smad3 axis may also participate in the regulation of ferroptosis. Studies have shown that ferroptosis is closely related to many diseases such as cancer, neurodegenerative diseases, inflammatory diseases, and autoimmune diseases. Considering the pivotal role of ferroptosis-regulating signaling in the pathogenesis of diverse diseases, the development of ferroptosis inducers or inhibitors may have significant clinical potential for the treatment of the aforementioned conditions.

6.
Acta Pharmacol Sin ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632318

RESUMO

Frizzled receptors (FZDs) are key contributors intrinsic to the Wnt signaling pathway, activation of FZDs triggering the Wnt signaling cascade is frequently observed in human tumors and intimately associated with an aggressive carcinoma phenotype. It has been shown that the abnormal expression of FZD receptors contributes to the manifestation of malignant characteristics in human tumors such as enhanced cell proliferation, metastasis, chemotherapy resistance as well as the acquisition of cancer stemness. Given the essential roles of FZD receptors in the Wnt signaling in human tumors, this review aims to consolidate the prevailing knowledge on the specific status of FZD receptors (FZD1-10) and elucidate their respective functions in tumor progression. Furthermore, we delineate the structural basis for binding of FZD and its co-receptors to Wnt, and provide a better theoretical foundation for subsequent studies on related mechanisms. Finally, we describe the existing biological classes of small molecule-based FZD inhibitors in detail in the hope that they can provide useful assistance for design and development of novel drug candidates targeted FZDs.

7.
RSC Med Chem ; 15(4): 1096-1108, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38665824

RESUMO

Tumor cells hijack the programmed cell death protein-1 (PD-1)/programmed cell death ligand-1 (PD-L1) pathway to suppress the immune response through overexpressing PD-L1 to interact with PD-1 of T cells. With in-depth ongoing research, tumor-intrinsic PD-L1 is found to play important roles in tumor progression without interaction with PD-1 expressed on T cells, which provides an additional important target and therapeutic approach for development of PD-L1 inhibitors. Existing monoclonal antibody (mAb) drugs against the PD-1/PD-L1 pathway generally behave by conformationally blocking the interactions of PD-1 with PD-L1 on the cell surface. Beyond general inhibition of the protein-protein interaction (PPI), inhibitors targeting PD-L1 currently focus on the functional inhibition of the interaction between PD-1/PD-L1 and degradation of tumor-intrinsic PD-L1. This perspective will clarify the evolution of PD-L1 inhibitors and provide insights into the current development of PD-L1 inhibitors, especially targeting internalization and degradation of PD-L1.

8.
Coron Artery Dis ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38682469

RESUMO

BACKGROUND: The optimal timing for percutaneous coronary intervention (PCI) in patients undergoing transcatheter aortic valve replacement (TAVR) remains uncertain. This research aims to evaluate the results of patients diagnosed with severe aortic valve stenosis and coronary artery disease who undergo either simultaneous or staged PCI therapy during TAVR procedures. METHODS: We retrieved all relevant studies from our self-constructed databases up to January 2, 2024, encompassing databases such as Embase, Medline, Cochrane Library, and PubMed. RESULTS: A total of nine studies were included, and the results showed that both surgical modalities had good safety profiles in the early and long-term stages. For early endpoint events, the risk of all-cause mortality and major bleeding within 30 years was similar in the staged TAVR + PCI and the contemporaneous TAVR + PCI (P > 0.05). Additionally, the risk of myocardial infarction, stroke, acute kidney injury and pacemaker implantation within 30 days or perioperatively is similar (P > 0.05). For long-term endpoint events, the risk of all-cause mortality, myocardial infarction and stroke was similar in the two groups at ≥2 years (P > 0.05). CONCLUSION: In patients undergoing TAVR who required coronary revascularization, no significant differences were observed in the early and long-term outcomes between those receiving concurrent TAVR and PCI versus staged surgery.

9.
Bioorg Chem ; 147: 107314, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38581967

RESUMO

The identification of novel 4-hydroxy-2-quinolone-3-carboxamide antibacterials with improved properties is of great value for the control of antibiotic resistance. In this study, a series of N-heteroaryl-substituted 4-hydroxy-2-quinolone-3-carboxamides were developed using the bioisosteric replacement strategy. As a result of our research, we discovered the two most potent GyrB inhibitors (WBX7 and WBX18), with IC50 values of 0.816 µM and 0.137 µM, respectively. Additional antibacterial activity screening indicated that WBX18 possesses the best antibacterial activity against MRSA, VISA, and VRE strains, with MIC values rangingbetween0.5and 2 µg/mL, which was 2 to over 32 times more potent than that of vancomycin. In vitro safety and metabolic stability, as well as in vivo pharmacokinetics assessments revealed that WBX18 is non-toxic to HUVEC and HepG2, metabolically stable in plasma and liver microsomes (mouse), and displays favorable in vivo pharmacokinetic properties. Finally, docking studies combined with molecular dynamic simulation showed that WBX18 could stably fit in the active site cavity of GyrB.


Assuntos
Antibacterianos , DNA Girase , Testes de Sensibilidade Microbiana , Inibidores da Topoisomerase II , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Humanos , DNA Girase/metabolismo , Inibidores da Topoisomerase II/farmacologia , Inibidores da Topoisomerase II/química , Inibidores da Topoisomerase II/síntese química , Relação Estrutura-Atividade , Animais , Estrutura Molecular , Relação Dose-Resposta a Droga , Camundongos , Células Hep G2 , Simulação de Acoplamento Molecular , Microssomos Hepáticos/metabolismo , Microssomos Hepáticos/química
10.
J Colloid Interface Sci ; 665: 100-108, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38518422

RESUMO

Construction of inorganic/organic heterostructures has been proven to be a very promising strategy to design highly efficient photocatalysts for solar driven hydrogen evolution from water. Herein, we report the preparation of a direct Z-scheme heterojunction photocatalyst by in situ growth of cadmium sulfide on a triazine-based covalent organic framework (COF). The triazine based-COF was synthesized by condensation reaction of precursors 1,3,5-tris-(4-formyl-phenyl) triazine (TFPT) and 2,5-bis-(3-hydroxypropoxy) terephthalohydrazide (DHTH), termed as TFPT-DHTH-COF. Widely distributed nitrogen atoms throughout TFPT-DHTH-COF skeletons serve as anchoring sites for strong interfacial interactions with CdS. The CdS/TFPT-DHTH-COF composite showed a hydrogen evolution rate of 15.75 mmol h-1 g-1, which is about 75 times higher than that of TFPT-DHTH-COF (0.21 mmol h-1 g-1) and 3.4 times higher than that of CdS (4.57 mmol h-1 g-1). With the properly staggered band alignment and strong interfacial interaction between TFPT-DHTH-COF and CdS, a Z-scheme charge transfer pathway is achieved. The mechanism has been systematically analyzed by steady state and time-resolved photoluminescence measurements as well as in situ irradiated X-ray photoelectron spectroscopy.

11.
J Transl Med ; 22(1): 216, 2024 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424632

RESUMO

Lung adenocarcinoma (LUAD) is the most common pathological type of lung cancer, but the early diagnosis rate is low. The RNA-binding ubiquitin ligase MEX3C promotes tumorigenesis in several cancers but its mechanism of action in LUAD is unclear. In this study, the biological activity of MEX3C was assessed in LUAD. MEX3C and RUNX3 mRNA levels in the tissues of LUAD patients were determined using reverse transcription­quantitative PCR. The involvement of MEX3C in the growth and metastasis of LUAD cells was measured by EdU assay, CCK-8, colony formation, Transwell assay, TUNEL, and flow cytometry. Expression of apoptosis and epithelial-mesenchymal transition related proteins were determined using western blotting analysis. LUAD cells transfected with si-MEX3C were administered to mice subcutaneously to monitor tumor progression and metastasis. We found that MEX3C is strongly upregulated in LUAD tissue sections, and involved in proliferation and migration. A549 and H1299 cells had significantly higher levels of MEX3C expression compared to control HBE cells. Knockdown of MEX3C dramatically decreased cell proliferation, migration, and invasion, and accelerated apoptosis. Mechanistically, we demonstrate MEX3C induces ubiquitylation and degradation of tumor suppressor RUNX3. Moreover, RUNX3 transcriptionally represses Suv39H1, as revealed by RNA pull-down and chromatin immunoprecipitation assays. The in vivo mice model demonstrated that knockdown of MEX3C reduced LUAD growth and metastasis significantly. Collectively, we reveal a novel MEX3C-RUNX3-Suv39H1 signaling axis driving LUAD pathogenesis. Targeting MEX3C may represent a promising therapeutic strategy against LUAD.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , MicroRNAs , Animais , Humanos , Camundongos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica , Ligases/genética , Ligases/metabolismo , Neoplasias Pulmonares/patologia , MicroRNAs/genética , RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ubiquitina/genética , Ubiquitina/metabolismo , Ubiquitinação
12.
Nat Metab ; 6(2): 359-377, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38409323

RESUMO

High protein intake is common in western societies and is often promoted as part of a healthy lifestyle; however, amino-acid-mediated mammalian target of rapamycin (mTOR) signalling in macrophages has been implicated in the pathogenesis of ischaemic cardiovascular disease. In a series of clinical studies on male and female participants ( NCT03946774 and NCT03994367 ) that involved graded amounts of protein ingestion together with detailed plasma amino acid analysis and human monocyte/macrophage experiments, we identify leucine as the key activator of mTOR signalling in macrophages. We describe a threshold effect of high protein intake and circulating leucine on monocytes/macrophages wherein only protein in excess of ∼25 g per meal induces mTOR activation and functional effects. By designing specific diets modified in protein and leucine content representative of the intake in the general population, we confirm this threshold effect in mouse models and find ingestion of protein in excess of ∼22% of dietary energy requirements drives atherosclerosis in male mice. These data demonstrate a mechanistic basis for the adverse impact of excessive dietary protein on cardiovascular risk.


Assuntos
Doenças Cardiovasculares , Humanos , Masculino , Feminino , Camundongos , Animais , Leucina/metabolismo , Leucina/farmacologia , Fatores de Risco , Serina-Treonina Quinases TOR/metabolismo , Macrófagos/metabolismo , Fatores de Risco de Doenças Cardíacas , Mamíferos/metabolismo
13.
RSC Adv ; 14(7): 4880-4889, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38323015

RESUMO

Microencapsulation has been widely used to protect essential oils, facilitating their application in cosmetics. In this study, gelatin, gum arabic and n-butyl cyanoacrylate were used as wall materials, and composite microcapsules of tea tree essential oil (TTO) were prepared using a combination of composite coagulation and in situ polymerization methods. When the ratio of gelatin to gum arabic is 1 : 1, the ratio of TTO to n-butyl cyanoacrylate is 4 : 1, the curing time is 10 h, and the encapsulation efficiency (EE) under these conditions is 73.61%. Morphological observation showed that the composite capsule was a micron-sized spherical particle with an average particle size of 10.51 µm, and Fourier transform infrared spectroscopy (FT-IR) confirmed a complex coagulation reaction between gelatin and gum arabic, and the disappearance of the n-butyl cyanoacrylate peak indicated that the film was formed in a condensation layer. The thermogravimetric analysis (TGA) results showed that the composite capsule greatly improved the thermal stability of TTO. Rheological testing showed that the viscosity and viscoelasticity of the surface composite capsules have been improved. In addition, the composite capsule showed good stability in the osmotic environment and has good sustained-release performance and antioxidant capacity in the average human skin environment.

14.
EMBO Mol Med ; 16(2): 361-385, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38177538

RESUMO

Inflammation in the testes induced by infection and autoimmunity contributes significantly to male infertility, a public health issue. Current therapies using antibiotics and broad-spectrum anti-inflammatory drugs are ineffective against non-bacterial orchitis and induce side effects. This highlights the need to explore the pathogenesis of orchitis and develop alternative therapeutic strategies. In this study, we demonstrated that Gasdermin D (GSDMD) was activated in the testes during uropathogenic Escherichia coli (UPEC)-induced acute orchitis, and that GSDMD in macrophages induced inflammation and affected spermatogenesis during acute and chronic orchitis. In testicular macrophages, GSDMD promoted inflammation and antigen presentation, thereby enhancing the T-cell response after orchitis. Furthermore, the pharmacological inhibition of GSDMD alleviated the symptoms of UPEC-induced acute orchitis. Collectively, these findings provide the first demonstration of GSDMD's role in driving orchitis and suggest that GSDMD may be a potential therapeutic target for treating orchitis.


Assuntos
Orquite , Masculino , Humanos , Orquite/microbiologia , Orquite/patologia , Gasderminas , Apresentação de Antígeno , Inflamação , Macrófagos , Piroptose
15.
J Med Chem ; 67(2): 816-837, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38181380

RESUMO

Casitas B cell lymphoma-b (Cbl-b) is a vital negative regulator of TCR and BCR signaling pathways, playing a significant role in setting an appropriate threshold for the activation of T cells and controlling the tolerance of peripheral T cells via a variety of mechanisms. Overexpression of Cbl-b leads to immune hyporesponsiveness of T cells. Conversely, the deficiency of Cbl-b in T cells results in markedly increased production of IL-2, even in the lack of CD28 costimulation in vitro. And Cbl-b-/- mice spontaneously reject multifarious cancers. Therefore, Cbl-b may be associated with immune-mediated diseases, and blocking Cbl-b could be considered as a new antitumor immunotherapy strategy. In this review, the possible regulatory mechanisms and biological potential of Cbl-b for antitumor immunotherapy are summarized. Besides, the potential roles of Cbl-b in immune-mediated diseases are comprehensively discussed, with emphasis on Cbl-b immune-oncology agents in the preclinical stage and clinical trials.


Assuntos
Linfoma de Células B , Proteínas Proto-Oncogênicas c-cbl , Animais , Camundongos , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linfócitos T/metabolismo , Linfoma de Células B/tratamento farmacológico , Imunoterapia
16.
Nat Prod Rep ; 41(5): 784-812, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38275179

RESUMO

Covering 1963 to 2023Monoterpene indole alkaloids are the main sub-family of indole alkaloids with fascinating structures, stereochemistry, and diverse bioactivities (e.g., anticancer, anti-malarial and anti-arrhythmic etc.). Vallesamidine alkaloids and structurally more complex schizozygane alkaloids are small groups of rearranged monoterpene indole alkaloids with a unique 2,2,3-trialkylated indoline scaffold, while schizozygane alkaloids can generate a further rearranged skeleton, isoschizozygane, possessing a tetra-substituted, bridged tetrahydroquinoline core. In this review, the origin and structural features of vallesamidine and schizozygane alkaloids are introduced, and a discussion on the relationship of these alkaloids with aspidosperma alkaloids and a structural rearrangement hypothesis based on published studies is followed. Moreover, uncommon skeletons and potential bioactivities, such as anti-malarial and anti-tumour activities, make such alkaloids important synthetic targets, attracting research groups globally to accomplish total synthesis, resulting in impressive works on novel total synthesis, formal synthesis, and construction of key intermediates. These synthetic endeavours are systematically reviewed and highlighted with key strategies and efficiencies, providing different viewpoints on molecular structures and promoting the extension of chemical space and mining of new active scaffolds.


Assuntos
Alcaloides Indólicos , Antimaláricos/farmacologia , Antimaláricos/química , Antimaláricos/síntese química , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacologia , Alcaloides Indólicos/síntese química , Estrutura Molecular , Monoterpenos/química , Monoterpenos/farmacologia , Monoterpenos/síntese química
17.
Sci Total Environ ; 912: 169090, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38056661

RESUMO

The Chinese government claimed to reach carbon dioxide emissions peaking by 2030 and achieve carbon neutralization by 2060. In this context, it's meaningful and urgent to estimate GHG emissions amount in every sectors. The growing concern about reducing GHG emissions has been shared by many water companies. This work aims to identify and estimate GHG emissions from the activities of drinking water treatment plants (DWTPs). According to the GHG protocol, the GHG emission inventory of DWTPs covers the sources of fossil fuel combustion, reservoir emissions, electricity and heat supply, use of chemicals and additives, disposal of waste, transportation, operation and maintenance. The tool was tested by nine DWTPs, which had an average GHG emission intensity of 0.225 kg CO2-eq/m3. The GHG emission intensities range from 0.167 kg CO2-eq/m3 to 0.272 kg CO2-eq/m3. The main source of GHG emissions is electricity supply, followed by the use of chemicals and additives. According to the average emission intensity, the estimated total amount of GHG emissions from DWTPs in China is about 1.82 × 107 t/a, corresponding to 0.15 % of the total GHG emission in China. The proposed GHG sources and emissions help decision-makers and DWTPs companies estimate GHG emissions more accurately and undertake GHG reduction measures.


Assuntos
Água Potável , Gases de Efeito Estufa , Gases de Efeito Estufa/análise , Dióxido de Carbono/análise , China , Eletricidade , Efeito Estufa
18.
Ageing Res Rev ; 93: 102148, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38036104

RESUMO

Biomarkers are emerging as a potential tool for screening or diagnosing sarcopenia. We aimed to summarize the current evidence on the diagnostic test accuracy of biomarkers for sarcopenia. We comprehensively searched Ovid MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials up to January 2023 and only included diagnostic test accuracy studies. We identified 32 studies with 23,840 participants (women, 58.26%) that assessed a total of 30 biomarkers. The serum creatinine to cystatin C ratio (Cr/CysC) demonstrated a pooled sensitivity ranging from 51% (95% confidence interval [CI] 44-59%) to 86% (95% CI 70-95%) and a pooled specificity ranged from 55% (95% CI 38-70%) to 76% (95% CI 63-86%) for diagnosing sarcopenia defined by five different diagnostic criteria (11 studies, 7240 participants). The aspartate aminotransferase to alanine aminotransferase ratio demonstrated a pooled sensitivity of 62% (95% CI 56-67%) and a pooled specificity of 66% (95% CI 60-72%) (3 studies, 11,146 participants). The other 28 blood biomarkers exhibited low-to-moderate diagnostic accuracy for sarcopenia regardless of the reference standards. In conclusion, none of these biomarkers are optimal for screening or diagnosing sarcopenia. Well-designed studies are needed to explore and validate novel biomarkers for sarcopenia.


Assuntos
Sarcopenia , Humanos , Feminino , Sensibilidade e Especificidade , Sarcopenia/diagnóstico , Biomarcadores , Testes Diagnósticos de Rotina
19.
Commun Biol ; 6(1): 1258, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38086992

RESUMO

The mechanisms leading to changes in mesoscale chromatin organization during cellular aging are unknown. Here, we used transcriptional activator-like effectors, RNA-seq and superresolution analysis to determine the effects of genotoxic stress on oocyte chromatin structure. Major satellites are organized into tightly packed globular structures that coalesce into chromocenters and dynamically associate with the nucleolus. Acute irradiation significantly enhanced chromocenter mobility in transcriptionally inactive oocytes. In transcriptionally active oocytes, irradiation induced a striking unfolding of satellite chromatin fibers and enhanced the expression of transcripts required for protection from oxidative stress (Fermt1, Smg1), recovery from DNA damage (Tlk2, Rad54l) and regulation of heterochromatin assembly (Zfp296, Ski-oncogene). Non-irradiated, senescent oocytes exhibit not only high chromocenter mobility and satellite distension but also a high frequency of extra chromosomal satellite DNA. Notably, analysis of biological aging using an oocyte-specific RNA clock revealed cellular communication, posttranslational protein modifications, chromatin and histone dynamics as the top cellular processes that are dysregulated in both senescent and irradiated oocytes. Our results indicate that unfolding of heterochromatin fibers following acute genotoxic stress or cellular aging induced the formation of distended satellites and that abnormal chromatin structure together with increased chromocenter mobility leads to chromosome instability in senescent oocytes.


Assuntos
Heterocromatina , Oócitos , Animais , Heterocromatina/genética , Heterocromatina/metabolismo , Cromatina/genética , Cromatina/metabolismo , Histonas/metabolismo , Montagem e Desmontagem da Cromatina , Mamíferos/genética
20.
Sci Rep ; 13(1): 21443, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052924

RESUMO

The intricate involvement of Rho GTPases in a multitude of human malignancies and their diverse array of biological functions has garnered substantial attention within the scientific community. However, their expression pattern and potential role in gastric cancer (GC) remain unclear. In this study, we successfully identified two distinct subtypes associated with Rho GTPase-related gene (RGG) through consensus clustering analysis, which exhibited significant disparities in overall survival and the tumor microenvironment. Subsequently, an extensively validated risk model termed RGGscore was meticulously constructed to prognosticate the outcomes of GC patients. This model was further assessed and validated using an external cohort. Notably, the high RGGscore group was indicative of a poorer prognosis. Univariate and multivariate Cox regression analyses unveiled the RGGscore as an autonomous prognostic indicator for GC patients. Subsequent external validation, utilizing two cohorts of patients who underwent immunotherapy, demonstrated a significant correlation between a low RGGscore and improved response to immunotherapy. Additionally, the expression levels of three genes associated with RGGscore were examined using qRT-PCR. Taken together, a pioneering RGGscore model has been successfully established, showcasing its potential efficacy in offering valuable therapeutic guidance for GC.


Assuntos
Carcinoma , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Análise por Conglomerados , Imunoterapia , Microambiente Tumoral , Proteínas rho de Ligação ao GTP/genética , Prognóstico
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