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1.
Crit Rev Oncol Hematol ; 204: 104525, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39370059

RESUMO

Meta-analyses have reported conflicting data on the whole blood cell count (WBCC) derived indexes (neutrophil-to-lymphocyte ratio [NLR], platelet-to-lymphocyte ratio [PLR], and lymphocyte-to-monocyte ratio [LMR]) and cancer prognosis. However, the strength and quality of this evidence has not been quantified in aggregate. To grade the evidence from published meta-analyses of cohort studies that investigated the associations between NLR, PLR, and LMR and cancer prognosis. A total of 694 associations from 224 articles were included. And 219 (97.8%) articles rated as moderate-to-high quality according to AMSTAR. There were four associations supported by convincing evidence. Meanwhile, 165 and 164 associations were supported by highly suggestive and suggestive evidence, respectively. In this umbrella review, we summarized the existing evidence on the WBCC-derived indexes and cancer prognosis. Due to the direction of effect sizes is not completely consistent between studies, further research is needed to assess causality and provide firm evidence.

2.
J Sci Food Agric ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39364803

RESUMO

BACKGROUND: This study investigated the contribution of 11 polysaccharides (2%, w/w), including pectin (PC), κ-carrageenan (KC), ι-carrageenan (IC), gellan gum (GG), guar gum (GM), sodium alginate (SA), konjac gum (KG), gum arabic (GA), fucoidan (FC), locust bean gum (LBG), and curdlan (CD), to the gel and microstructural properties of Meretrix meretrix clam gel (MMG). RESULTS: The hardness, springiness and chewiness of MMG with KC, IC, GG, SA and FC addition increased by ~10%-250%, while PC, GM, KG and LBG groups decreased by ~0.6% to 69%. KC, IC, SA, GG and FC decreased the cooking loss rate (CLR) by 69.4% to 88.7% and correspondingly enhanced the water holding capacity (WHC) by 10.2% to 21.4%, which was accompanied by an increased bound water and immobilized water area and high hydrogen proton density. The addition of KC transformed the MMG microstructure from a loose network with large pores to a compact, dense network, reducing lacunarity by 57.9%. The primary intermolecular forces in MMG with the incorporation of KC, IC, GG, SA and FC were hydrophobic interactions and disulfide bonds, which increased by 32.8%-105.3% and 45.6%-114.5% than MMG alone, respectively. CONCLUSION: Collectively, KC, IC, GG, SA and FC could improve the gel properties of MMG and the strongest synergistic combination was found in the MMG/KC system. This study suggests that the incorporation of polysaccharides is a strategy with potential for modifying the gel properties of shellfish surimi products. © 2024 Society of Chemical Industry.

3.
J Sci Food Agric ; 2024 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-39425557

RESUMO

BACKGROUND: Previous studies have investigated complexation and coacervation of scallop Patinopecten yessoensis male gonad hydrolysates (SMGHs) and polysaccharides influenced by pH and blending ratio. It has been found that SMGHs/polysaccharide composite shows better gel properties under strongly acidic conditions. Thus, the complexation and coacervation of SMGHs and gellan gum (GG) were investigated via turbidimetric titration at different pH values (1-12) and biopolymer blending ratios (9.5:0.5-6:4). RESULTS: Both pHc and pHφ1 exhibited ratio-independent behavior with constant values at approximately pH 5.8 and pH 3.8, respectively, dividing SMGHs/GG blends into three phases named mixed polymers, soluble complexes and insoluble coacervates, respectively. Overall, SMGHs and GG exhibited synergistic gelation under neutral and acidic conditions, with the initial storage modulus (G') increasing by approximately 42.5-, 573.7- and 3421-fold and 97.7-, 550.3- and 0.5-fold, respectively, at pH 7, 5 and 3, compared with SMGHs and GG. As pH decreased from 7 to 3, the initial G' and viscosity η values of SMGHs/GG gels increased by 20.1- and 2.3-fold, respectively, exhibiting the greatest increase in gel strength. Moreover, the free water in the SMGHs/GG system significantly shifted toward lower relaxation times attributed to the immobilization of the outer hydration layers. SMGHs/GG gels in the insoluble phase exhibited denser networks and rougher surfaces, supporting the enhanced rheological properties and water retention capacity of the gel. CONCLUSION: This work provides a basic foundation for the development of pH-driven SMGHs/GG gelation by examining complexation and coacervation processes. © 2024 Society of Chemical Industry.

4.
Cancers (Basel) ; 16(17)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39272801

RESUMO

BACKGROUND: Currently, prostate cancer (PCa) prebiopsy medical image diagnosis mainly relies on mpMRI and PI-RADS scores. However, PI-RADS has its limitations, such as inter- and intra-radiologist variability and the potential for imperceptible features. The primary objective of this study is to evaluate the effectiveness of a machine learning model based on radiomics analysis of MRI T2-weighted (T2w) images for predicting PCa in prebiopsy cases. METHOD: A retrospective analysis was conducted using 820 lesions (363 cases, 457 controls) from The Cancer Imaging Archive (TCIA) Database for model development and validation. An additional 83 lesions (30 cases, 53 controls) from Hong Kong Queen Mary Hospital were used for independent external validation. The MRI T2w images were preprocessed, and radiomic features were extracted. Feature selection was performed using Cross Validation Least Angle Regression (CV-LARS). Using three different machine learning algorithms, a total of 18 prediction models and 3 shape control models were developed. The performance of the models, including the area under the curve (AUC) and diagnostic values such as sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), were compared to the PI-RADS scoring system for both internal and external validation. RESULTS: All the models showed significant differences compared to the shape control model (all p < 0.001, except SVM model PI-RADS+2 Features p = 0.004, SVM model PI-RADS+3 Features p = 0.002). In internal validation, the best model, based on the LR algorithm, incorporated 3 radiomic features (AUC = 0.838, sensitivity = 76.85%, specificity = 77.36%). In external validation, the LR (3 features) model outperformed PI-RADS in predictive value with AUC 0.870 vs. 0.658, sensitivity 56.67% vs. 46.67%, specificity 92.45% vs. 84.91%, PPV 80.95% vs. 63.64%, and NPV 79.03% vs. 73.77%. CONCLUSIONS: The machine learning model based on radiomics analysis of MRI T2w images, along with simulated biopsy, provides additional diagnostic value to the PI-RADS scoring system in predicting PCa.

5.
J Transl Med ; 22(1): 860, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39334418

RESUMO

BACKGROUND: There is currently a lack of comprehensive evidence regarding the correlation between Alternate Mediterranean Diet (AMED) and the survival of patients with ovarian cancer (OC). This prospective cohort study first assessed the association of AMED, not only pre-diagnosis and post-diagnosis but also the change from pre-diagnosis to post-diagnosis with OC survival. METHODS: A total of 560 OC patients were included in the study, and their dietary intake was assessed using a reliable 111-item food frequency questionnaire. The overall survival (OS) of the patients was monitored through active follow-up and review of medical records until February 16th, 2023. Cox proportional hazard regression models were utilized to compute the hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs). RESULTS: Out of the total 560 patients with OC, 211 (37.68%) succumbed during a median follow-up period of 44.40 months (interquartile range: 26.97-61.37). Comparative analysis indicated a significant association between the highest tertiles of pre-diagnosis (HR = 0.59; 95% CI 0.38-0.90; Ptrend < 0.05) and post-diagnosis (HR = 0.61; 95% CI 0.41-0.91; Ptrend < 0.05) AMED intake and improved OS as opposed to the lowest tertile. Additionally, a significant linear trend was observed for AMED and OC survival. Notably, decreased intake (more than 5% change) and significantly increased intake (more than 15% change) of AMED from pre-diagnosis to post-diagnosis were linked to worse and better OS, respectively, when compared to the stable intake group (change within 5%). Furthermore, patients displaying consistently higher AMED intake both before and after diagnosis experienced enhanced OS in comparison to those with consistently low AMED intake (HRHigh-High vs. Low-Low = 0.47; 95% CI 0.31-0.70). CONCLUSION: High pre-diagnosis and post-diagnosis AMED was associated with an improved OS in patients with OC, suggesting that maintaining a consistently high intake of AMED could potentially benefit the prognosis of OC.


Assuntos
Dieta Mediterrânea , Neoplasias Ovarianas , Humanos , Feminino , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/dietoterapia , Estudos Prospectivos , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Análise de Sobrevida , Adulto , Estimativa de Kaplan-Meier , Idoso
6.
Biomed Pharmacother ; 179: 117311, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39182322

RESUMO

The underlying mechanisms of diseases affecting the central nervous system (CNS) remain unclear, limiting the development of effective therapeutic strategies. Remarkably, cellular senescence, a biological phenomenon observed in cultured fibroblasts in vitro, is a crucial intrinsic mechanism that influences homeostasis of the brain microenvironment and contributes to the onset and progression of CNS diseases. Cellular senescence has been observed in disease models established in vitro and in vivo and in bodily fluids or tissue components from patients with CNS diseases. These findings highlight cellular senescence as a promising target for preventing and treating CNS diseases. Consequently, emerging novel therapies targeting senescent cells have exhibited promising therapeutic effects in preclinical and clinical studies on aging-related diseases. These innovative therapies can potentially delay brain cell loss and functional changes, improve the prognosis of CNS diseases, and provide alternative treatments for patients. In this study, we examined the relevant advancements in this field, particularly focusing on the targeting of senescent cells in the brain for the treatment of chronic neurodegenerative diseases (e.g., Alzheimer's disease, Parkinson's disease, and multiple sclerosis) and acute neurotraumatic insults (e.g., ischemic stroke, spinal cord injury, and traumatic brain injury).


Assuntos
Senescência Celular , Doenças do Sistema Nervoso Central , Humanos , Senescência Celular/efeitos dos fármacos , Animais , Doenças do Sistema Nervoso Central/patologia , Doenças do Sistema Nervoso Central/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/patologia , Encéfalo/patologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo
7.
Cell Res ; 34(10): 707-724, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39103524

RESUMO

The hierarchical packaging of chromatin fibers plays a critical role in gene regulation. The 30-nm chromatin fibers, a central-level structure bridging nucleosomal arrays to higher-order organizations, function as the first level of transcriptional dormant chromatin. The dynamics of 30-nm chromatin fiber play a crucial role in biological processes related to DNA. Here, we report a 3.6-angstrom resolution cryogenic electron microscopy structure of H5-bound dodecanucleosome, i.e., the chromatin fiber reconstituted in the presence of linker histone H5, which shows a two-start left-handed double helical structure twisted by tetranucleosomal units. An atomic structural model of the H5-bound chromatin fiber, including an intact chromatosome, is built, which provides structural details of the full-length linker histone H5, including its N-terminal domain and an HMG-motif-like C-terminal domain. The chromatosome structure shows that H5 binds the nucleosome off-dyad through a three-contact mode in the chromatin fiber. More importantly, the H5-chromatin structure provides a fine molecular basis for the intra-tetranucleosomal and inter-tetranucleosomal interactions. In addition, we systematically validated the physiological functions and structural characteristics of the tetranucleosomal unit through a series of genetic and genomic studies in Saccharomyces cerevisiae and in vitro biophysical experiments. Furthermore, our structure reveals that multiple structural asymmetries of histone tails confer a polarity to the chromatin fiber. These findings provide structural and mechanistic insights into how a nucleosomal array folds into a higher-order chromatin fiber with a polarity in vitro and in vivo.


Assuntos
Cromatina , Histonas , Nucleossomos , Nucleossomos/metabolismo , Nucleossomos/ultraestrutura , Nucleossomos/química , Histonas/metabolismo , Histonas/química , Cromatina/metabolismo , Cromatina/química , Microscopia Crioeletrônica , Ligação Proteica , Modelos Moleculares
8.
Food Funct ; 15(16): 8408-8417, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39040017

RESUMO

Background: Previous studies on the association between diet quality and ovarian cancer (OC) survival are limited and inconsistent. We evaluated the relationship between pre- and post-diagnosis diet quality based on the Healthy Eating Index-2020 (HEI-2020), as well as their changes and OC survival. Methods: This prospective cohort study involved 1082 patients with OC aged 18-79 years, enrolled between 2015 and 2022. Detailed dietary intake before and after diagnosis was recorded using a validated food frequency questionnaire. Deaths were ascertained until February 16th, 2023 via medical records and active follow-up. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CI). Results: We included 549 OC cases with a median follow-up of 44.9 months, representing 206 total deaths. Higher HEI scores were associated with better OS (pre-diagnosis: HRT3 vs. T1 0.66, 95%CI: 0.46-0.93, HR1-SD 0.84, 95%CI: 0.73-0.96; post-diagnosis: HRT3 vs. T1 0.68, 95%CI: 0.49-0.96, HR1-SD 0.80, 95%CI: 0.69-0.92). Compared to the stable group, the group with decreased HEI scores (>3%) from pre- to post-diagnosis had worse OS (HR 1.93, 95%CI: 1.26-2.97). Conclusion: High pre- and post-diagnosis diet quality was associated with improved OC survival, whereas deterioration in diet quality after diagnosis was associated with decreased OC survival.


Assuntos
Dieta Saudável , Neoplasias Ovarianas , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto , Neoplasias Ovarianas/mortalidade , Idoso , Adolescente , Adulto Jovem , Modelos de Riscos Proporcionais
9.
bioRxiv ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38979269

RESUMO

Genome editing is poised to revolutionize treatment of genetic diseases, but poor understanding and control of DNA repair outcomes hinders its therapeutic potential. DNA repair is especially understudied in nondividing cells like neurons, which must withstand decades of DNA damage without replicating. This lack of knowledge limits the efficiency and precision of genome editing in clinically relevant cells. To address this, we used induced pluripotent stem cells (iPSCs) and iPSC-derived neurons to examine how postmitotic human neurons repair Cas9-induced DNA damage. We discovered that neurons can take weeks to fully resolve this damage, compared to just days in isogenic iPSCs. Furthermore, Cas9-treated neurons upregulated unexpected DNA repair genes, including factors canonically associated with replication. Manipulating this response with chemical or genetic perturbations allowed us to direct neuronal repair toward desired editing outcomes. By studying DNA repair in postmitotic human cells, we uncovered unforeseen challenges and opportunities for precise therapeutic editing.

10.
Int J Biol Macromol ; 273(Pt 2): 133162, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38878925

RESUMO

Calcium ß-hydroxy-ß-methylbutyrate (CaHMB), a functional calcium salt, is used to maintain and improve muscle health. Here, a new hydrogel material prepared from alginate (ALG) with three M/G ratios (1:1, 2:1, and 1:2) and CaHMB (0-2 mg/mL) was investigated. CaHMB regulates the formation and properties of ALG hydrogels through chelation and hydrogen bonding. When the M/G ratio was 2:1, the anionic groups of CaHMB containing carboxyl and hydroxyl groups formed hydrogen bonds with the polysaccharide chains, hindering the capture of Ca2+ by the G-residue fragments of ALG, which in turn retarded the gelation process. The noncalcium cross-linked polysaccharide chain structure of ALG and the anionic group of CaHMB also affected the water distribution in the hydrogel, especially when M residue content ≥G residue content. Lower M/G ratios and higher CaHMB concentrations could increase the number of "egg box" crosslinking junctions of calcium alginate, and the microstructure was denser in the gel pores, resulting in a stronger gel strength and more free water bound in the gel matrix. This study provides a theoretical and methodological basis for the design of novel hydrogels by studying the crosslinking features of ALG/CaHMB.


Assuntos
Alginatos , Cálcio , Hidrogéis , Alginatos/química , Hidrogéis/química , Cálcio/química , Valeratos/química , Íons/química , Ligação de Hidrogênio , Água/química
11.
Biomaterials ; 311: 122664, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38889597

RESUMO

In order to guide the formulation of post-stroke treatment strategy in time, it is necessary to have real-time feedback on collateral circulation and revascularization. Currently used near-infrared II (NIR-II) probes have inherent binding with endogenous albumin, resulting in significant background signals and uncontrollable pharmacokinetics. Therefore, the albumin-escaping properties of the new probe, IR-808AC, was designed, which achieved timely excretion and low background signal, enabling the short-term repeatable injection for visualization of cerebral vessels and perfusion. We further achieved continuous observation of changes in collateral vessels and perfusion during the 7-d period in middle cerebral artery occlusion mice using IR-808AC in vivo. Furthermore, using IR-808AC, we confirmed that remote ischemic conditioning could promote collateral vessels and perfusion. Finally, we evaluated the revascularization after thrombolysis on time in embolic stroke mice using IR-808AC. Overall, our study introduces a novel methodology for safe, non-invasive, and repeatable assessment of collateral circulation and revascularization in real-time that is crucial for the optimization of treatment strategies.


Assuntos
Modelos Animais de Doenças , Acidente Vascular Cerebral , Animais , Acidente Vascular Cerebral/diagnóstico por imagem , Camundongos , Masculino , Imagem de Perfusão/métodos , Artérias Cerebrais/diagnóstico por imagem , Camundongos Endogâmicos C57BL , Albuminas/química , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Circulação Colateral
12.
J Hazard Mater ; 472: 134556, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38735187

RESUMO

BACKGROUND: Although evidence on the association between per- and polyfluoroalkyl substances (PFASs) and human health outcomes has grown exponentially, specific health outcomes and their potential associations with PFASs have not been conclusively evaluated. METHODS: We conducted a comprehensive search through the databases of PubMed, Embase, and Web of Science from inception to February 29, 2024, to identify systematic reviews with meta-analyses of observational studies examining the associations between the PFASs and multiple health outcomes. The quality of included studies was evaluated using the A Measurement Tool to Assess Systematic Reviews (AMSTAR) tool, and credibility of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) criteria. The protocol of this umbrella review (UR) had been registered in PROSPERO (CRD 42023480817). RESULTS: The UR identified 157 meta-analyses from 29 articles. Using the AMSTAR measurement tool, all articles were categorized as of moderate-to-high quality. Based on the GRADE assessment, significant associations between specific types of PFASs and low birth weight, tetanus vaccine response, and triglyceride levels showed high certainty of evidence. Moreover, moderate certainty of evidence with statistical significance was observed between PFASs and health outcomes including lower BMI z-score in infancy, poor sperm progressive motility, and decreased risk of preterm birth as well as preeclampsia. Fifty-two (33%) associations (e.g., PFASs and gestational hypertension, cardiovascular disease, etc) presented low certainty evidence. Additionally, eighty-five (55%) associations (e.g., PFASs with infertility, lipid metabolism, etc) presented very low certainty evidence. CONCLUSION: High certainty of evidence supported that certain PFASs were associated with the incidence of low birth weight, low efficiency of the tetanus vaccine, and low triglyceride levels.


Assuntos
Fluorocarbonos , Revisões Sistemáticas como Assunto , Humanos , Gravidez , Estudos Observacionais como Assunto , Metanálise como Assunto , Recém-Nascido de Baixo Peso , Feminino , Poluentes Ambientais , Toxoide Tetânico , Triglicerídeos/sangue
13.
J Tissue Eng ; 15: 20417314241237052, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481708

RESUMO

The incidence of ischemic stroke (IS) is rising in tandem with the global aging population. There is an urgent need to delve deeper into the pathological mechanisms and develop new neuroprotective strategies. In the present review, we discuss the latest advancements and research on various nanodrug delivery systems (NDDSs) for targeting microglial polarization in IS treatment. Furthermore, we critically discuss the different strategies. NDDSs have demonstrated exceptional qualities to effectively permeate the blood-brain barrier, aggregate at the site of ischemic injury, and target specific cell types within the brain when appropriately modified. Consequently, NDDSs have considerable potential for reshaping the polarization phenotype of microglia and could be a prospective therapeutic strategy for IS. The treatment of IS remains a challenge. However, this review provides a new perspective on neuro-nanomedicine for IS therapies centered on microglial polarization, thereby inspiring new research ideas and directions.

14.
Dalton Trans ; 53(2): 582-590, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38059743

RESUMO

Photodynamic therapy provides a promising solution for treating various cancer types. In this study, three distinct asymmetric porphyrin-cisplatin complex photosensitizers (ZnPt-P1, ZnPt-P2, and ZnPt-P3) were synthesized, each having unique side chains. Through a set of experiments involving singlet oxygen detection and density functional theory, ZnPt-P1 was demonstrated to have excellent efficacy, exceeding that of ZnPt-P2 and ZnPt-P3. Notably, ZnPt-1 showed significant phototoxicity while maintaining low dark toxicity when tested on HepG2 cells. Additionally, further examination revealed that ZnPt-P1 had the capability to generate reactive oxygen species within cancer cells when exposed to light irradiation. Taken together, these results highlight the potential of ZnPt-P1 as a photosensitizer for use in photodynamic therapy. This study contributes to enhancing cancer treatment methodologies and provides insights for the future development of innovative drugs for photosensitization.


Assuntos
Fotoquimioterapia , Porfirinas , Fármacos Fotossensibilizantes , Cisplatino/farmacologia , Porfirinas/química , Oxigênio Singlete/química
15.
Front Psychiatry ; 14: 1218551, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37706034

RESUMO

Objective: Gender differences are prevalent in major depressive disorder (MDD), but the gender differences in the relationship between comorbid anxiety and thyroid hormones in young first-episode and drug-naive (FEND) MDD patients are unknown. Methods: A total of 1,289 young outpatients with FEDN MDD were recruited. Demographic and clinical data were collected for each patient. The patient's blood glucose, blood pressure, thyroid hormone, and thyroid antibody levels were measured. The Hamilton depression scale (HAMD), Hamilton anxiety scale (HAMA), and Positive and Negative Syndrome Scale (PANSS) were used to assess patients' depression, anxiety, and positive symptoms, respectively. Results: The prevalence of comorbid anxiety disorders was 80.4 and 79.4% in male and female MDD patients, respectively. Patients with anxiety had higher HAMD and PANSS scores, higher serum thyroid stimulating hormone (TSH), anti-thyroglobulin antibody (A-TG), and thyroid peroxidase antibody (A-TPO) levels, higher blood glucose and blood pressure levels, and more patients with psychotic symptoms and suicide attempts. Male patients were younger and had a younger age of onset. Logistic regression analysis showed that HAMD score and comorbid suicide attempts were significant predictors of anxiety symptoms in both males and females, whereas A-TG predicted anxiety symptoms in female patients only. Limitations: No causal relationship could be drawn due to the cross-sectional design. Conclusion: This study showed gender differences in factors associated with anxiety symptoms in patients with MDD. Some factors were associated with anxiety symptoms in both male and female patients, while A-TG was only associated with anxiety symptoms in female patients.

16.
DNA Repair (Amst) ; 127: 103512, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37230009

RESUMO

In the baker's yeast Saccharomyces cerevisiae, NuA4 and SWR1-C, two multisubunit complexes, are involved in histone acetylation and chromatin remodeling, respectively. Eaf1 is the assembly platform subunit of NuA4, Swr1 is the assembly platform and catalytic subunit of SWR1-C, while Swc4, Yaf9, Arp4 and Act1 form a functional module, and is present in both NuA4 and SWR1 complexes. ACT1 and ARP4 are essential for cell survival. Deletion of SWC4, but not YAF9, EAF1 or SWR1 results in a severe growth defect, but the underlying mechanism remains largely unknown. Here, we show that swc4Δ, but not yaf9Δ, eaf1Δ, or swr1Δ cells display defects in DNA ploidy and chromosome segregation, suggesting that the defects observed in swc4Δ cells are independent of NuA4 or SWR1-C integrity. Swc4 is enriched in the nucleosome-free regions (NFRs) of the genome, including characteristic regions of RDN5s, tDNAs and telomeres, independently of Yaf9, Eaf1 or Swr1. In particular, rDNA, tDNA and telomere loci are more unstable and prone to recombination in the swc4Δ cells than in wild-type cells. Taken together, we conclude that the chromatin associated Swc4 protects nucleosome-free chromatin of rDNA, tDNA and telomere loci to ensure genome integrity.


Assuntos
Nucleossomos , Proteínas de Saccharomyces cerevisiae , Humanos , Histonas/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , DNA Ribossômico , Cromatina , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Telômero/genética , Telômero/metabolismo , Instabilidade Genômica , Montagem e Desmontagem da Cromatina , Histona Acetiltransferases/genética , Fatores de Transcrição/genética
17.
Inorg Chem ; 61(49): 20159-20168, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36450105

RESUMO

Two coordination polymers (CPs), namely, [Mn3(L)2(4,4'-bipy)2(H2O)2]n (1) and [Ni(L1)(1,4-bib)(H2O)]n (2) (H3L = 5-(3-bromo-4-carboxyphenoxy)isophthalic acid, H2L1 = 5-(3-hydroxyphenoxy)isophthalic acid, 4,4'-bpy = 4,4'-bipyridine, and 1,4-bib = 1,4-bis(1H-imidazol-1-yl)benzene), were synthesized under hydrothermal conditions. Most notably, with the help of the bromine atom-inducing effect, ligand transformation was observed in the structure of complex 2, which was scrutinized thoroughly by single crystal X-ray crystallography and X-ray photoelectron spectroscopy (XPS). Strikingly, Ni(II) ions were utilized as both coordinated atoms and as a catalyst for in situ Br-OH exchange of H3L in the process, as a result of which the product would have preferred to form a one-dimensional chain. The same reaction cannot happen in 1, leading to form a two-dimensional structure. Moreover, Ni(II)-catalyzed and magnetic exchange mechanisms were well interpreted using density functional theory (DFT) calculations. Finally, complexes 1-2 show three-dimensional (3D) supramolecular structures because of intermolecular weak interactions (C-Br···π, C-H···π, C-H···O, and π···π stacking) and exhibit utterly different antiferrimagnetic coupling interactions.


Assuntos
Ácidos Ftálicos , Modelos Moleculares , Teoria da Densidade Funcional , Fenômenos Magnéticos
18.
Biochem J ; 479(23): 2433-2447, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36416748

RESUMO

The KEOPS complex is an evolutionarily conserved protein complex in all three domains of life (Bacteria, Archaea, and Eukarya). In budding yeast Saccharomyces cerevisiae, the KEOPS complex (ScKEOPS) consists of five subunits, which are Kae1, Bud32, Cgi121, Pcc1, and Gon7. The KEOPS complex is an ATPase and is required for tRNA N6-threonylcarbamoyladenosine modification, telomere length maintenance, and efficient DNA repair. Here, recombinant ScKEOPS full complex and Kae1-Pcc1-Gon7 and Bud32-Cgi121 subcomplexes were purified and their biochemical activities were examined. KEOPS was observed to have ATPase and GTPase activities, which are predominantly attributed to the Bud32 subunit, as catalytically dead Bud32, but not catalytically dead Kae1, largely eliminated the ATPase/GTPase activity of KEOPS. In addition, KEOPS could hydrolyze ADP to adenosine or GDP to guanosine, and produce PPi, indicating that KEOPS is an ADP/GDP nucleotidase. Further mutagenesis characterization of Bud32 and Kae1 subunits revealed that Kae1, but not Bud32, is responsible for the ADP/GDP nucleotidase activity. In addition, the Kae1V309D mutant exhibited decreased ADP/GDP nucleotidase activity in vitro and shortened telomeres in vivo, but showed only a limited defect in t6A modification, suggesting that the ADP/GDP nucleotidase activity of KEOPS contributes to telomere length regulation.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Adenosina Trifosfatases/metabolismo , Difosfato de Adenosina/metabolismo , GTP Fosfo-Hidrolases/metabolismo
19.
Abdom Radiol (NY) ; 47(10): 3615-3627, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35821274

RESUMO

PURPOSE: This study aimed to investigate whether underdilated transjugular intrahepatic portosystemic shunt (TIPS) could reduce the risk of hepatic encephalopathy (HE) and ameliorate impaired hepatic function in patients with a history of splenectomy. METHODS: A retrospective case-control study was conducted with 96 patients who had prior splenectomy and TIPS placement from August 2016 to May 2022. All patients were divided into two groups based on the diameter of expansion balloon catheters, the underdilated group (6-mm balloon catheter, n = 60) and a control group (8-mm balloon catheter, n = 36). Following the 1:1 propensity score matching (PSM), 33 patients in the underdilated group and 33 patients in the control group were included. RESULTS: During a median follow-up of 36 months, a quicker recovery in liver function after TIPS placement was showed in the underdilated group. The mean TBIL content (16.562 ± 6.549 µmol/L vs 23.871 ± 11.609 µmol/L, P = 0.019) and the mean CLIF-C AD score (41.108 ± 5.223 vs 45.100 ± 4.429, P = 0.033) in the underdilated group were significantly lower than those in the control group during 6 to 12 months after the procedure. In line with the control group, the ability to reduce portal pressure gradient (PPG) and achieve a significantly clinical remission of PVT and ascites severity was showed in the underdilated group 3 months after TIPS creation (P < 0.001). The Kaplan-Meier analysis demonstrated that no statistically significant differences were found in the cumulative incidence of no overt HE (OHE) (log-rank P = 0.383), cumulative incidence without shunt dysfunction (log-rank P = 0.283), cumulative incidence of no variceal rebleeding (log-rank P = 0.696), and survival (log-rank P = 0.341) (log-rank P = 0.341) between the two groups during the follow-up period. CONCLUSION: For patients with prior splenectomy, it is safe to employ underdilated TIPS, as the stents will eventually self-expand to 8 mm. The present study has shown some degree of liver function preservation in the underdilated group, which may be related to slower progressive changes in the portal hemodynamics.


Assuntos
Varizes Esofágicas e Gástricas , Encefalopatia Hepática , Hipertensão Portal , Derivação Portossistêmica Transjugular Intra-Hepática , Estudos de Casos e Controles , Encefalopatia Hepática/complicações , Encefalopatia Hepática/epidemiologia , Humanos , Hipertensão Portal/cirurgia , Cirrose Hepática/complicações , Derivação Portossistêmica Transjugular Intra-Hepática/métodos , Prognóstico , Pontuação de Propensão , Estudos Retrospectivos , Esplenectomia/efeitos adversos , Resultado do Tratamento
20.
Eur J Gastroenterol Hepatol ; 34(9): 948-955, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35594511

RESUMO

OBJECTIVE: To explore the predictive value of model for end-stage liver disease (MELD)-Sarcopenia score for survival of cirrhotic patients after transjugular intrahepatic portosystemic shunt (TIPS) placement. METHODS: 289 patients who underwent TIPS between February 2016 and December 2020 were included, they were divided into the sarcopenia group ( n = 138) and non-sarcopenia group ( n = 151) according to whether they were complicated with sarcopenia. Kaplan-Meier curve was used to analyze and compare the prognosis of the above two groups and multivariate Cox regression analysis was used to identify the independent prognostic factors. The performance of different predictive models was compared using C-index. RESULTS: During the follow-up, Kaplan-Meier analyses indicated that cumulative survival was significantly lower in sarcopenia group than that in non-sarcopenia group [74.6% vs. 92.7%, HR, 0.24 (95% confidence interval (CI), 0.12-0.46), Log-rank P < 0.001]. After multivariate Cox analysis, age [HR, 1.040 (95% CI, 1.015-1.065), P = 0.002], sarcopenia [HR, 3.948 (95% CI, 1.989-7.838), P < 0.001], albumin [HR, 0.945 (95% CI, 0.897-0.997), P = 0.037], and MELD score [HR, 1.156 (95% CI, 1.097-1.217), P < 0.001] were identified as the independent risk factors for mortality after TIPS. The C-indexes of MELD-Sarcopenia, Child-Pugh, MELD, MELD-Na, and the Freiburg index of post-TIPS survival (FIPS) scores were 0.782, 0.688, 0.719, 0.734, and 0.770, respectively. CONCLUSION: Sarcopenia is independently correlated with post-TIPS mortality, and MELD-Sarcopenia score showed the best performance in predicting post-TIPS mortality than the traditional predictive models.


Assuntos
Doença Hepática Terminal , Derivação Portossistêmica Transjugular Intra-Hepática , Sarcopenia , Doença Hepática Terminal/complicações , Doença Hepática Terminal/diagnóstico , Doença Hepática Terminal/cirurgia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Cirrose Hepática/cirurgia , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Prognóstico , Estudos Retrospectivos , Sarcopenia/diagnóstico , Sarcopenia/etiologia , Índice de Gravidade de Doença , Resultado do Tratamento
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