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1.
Nat Commun ; 15(1): 5727, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977669

RESUMO

DNA replication and transcription generate DNA supercoiling, which can cause topological stress and intertwining of daughter chromatin fibers, posing challenges to the completion of DNA replication and chromosome segregation. Type II topoisomerases (Top2s) are enzymes that relieve DNA supercoiling and decatenate braided sister chromatids. How Top2 complexes deal with the topological challenges in different chromatin contexts, and whether all chromosomal contexts are subjected equally to torsional stress and require Top2 activity is unknown. Here we show that catalytic inhibition of the Top2 complex in interphase has a profound effect on the stability of heterochromatin and repetitive DNA elements. Mechanistically, we find that catalytically inactive Top2 is trapped around heterochromatin leading to DNA breaks and unresolved catenates, which necessitate the recruitment of the structure specific endonuclease, Ercc1-XPF, in an SLX4- and SUMO-dependent manner. Our data are consistent with a model in which Top2 complex resolves not only catenates between sister chromatids but also inter-chromosomal catenates between clustered repetitive elements.


Assuntos
DNA Topoisomerases Tipo II , Heterocromatina , DNA Topoisomerases Tipo II/metabolismo , DNA Topoisomerases Tipo II/genética , Heterocromatina/metabolismo , Animais , Inibidores da Topoisomerase II/farmacologia , Sequências Repetitivas de Ácido Nucleico/genética , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/genética , Replicação do DNA , DNA Super-Helicoidal/metabolismo , DNA Super-Helicoidal/química , Humanos , Camundongos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , DNA/metabolismo , DNA/química , Interfase
2.
Heliyon ; 10(12): e33072, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38994059

RESUMO

High-polarity iridoids from Radix Scrophulariae (R. Scrophulariae) offer a range of benefits, including anti-inflammatory, antioxidant, antitumour, antibacterial, antiviral, and antiallergic effects. Although previous studies have indicated the potential of R. Scrophulariae for hyperthyroidism prevention and treatment, the specific active compounds involved and their mechanisms of action are not fully understood. This study explored the effects of high-polarity iridoid glycosides from R. Scrophulariae on hyperthyroidism induced in rats by levothyroxine sodium. The experimental design included a control group, a hyperthyroidism model group, and a group treated with iridoid glycosides. Serum triiodothyronine (T3) and thyroxine (T4) levels were quantified using an enzyme-linked immunosorbent assay (ELISA). Transcriptomic and proteomic analyses were applied to liver samples to identify differentially expressed genes and proteins. These analyses were complemented by trend analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. The effectiveness of key factors was further examined through molecular biology techniques. ELISA results indicated a notable increase in T3 and T4 in the hyperthyroid rats, which was significantly mitigated by treatment with iridoid glycosides. Transcriptomic analysis revealed 6 upregulated and 6 downregulated genes in the model group, showing marked improvement following treatment. Proteomic analysis revealed changes in 30 upregulated and 50 downregulated proteins, with improvements observed upon treatment. The PI3K-Akt signalling pathway was investigated through KEGG enrichment analysis. Molecular biology methods verified the upregulation of Spp1, Thbs1, PI3K, and Akt in the model group, which was reversed in the treatment group. This study revealed that highly polar iridoids from R. Scrophulariae can modulate the Spp1 gene and Thbs1 protein via the PI3K-Akt signalling pathway, suggesting a therapeutic benefit for hyperthyroidism and providing a basis for drug development targeting this condition.

3.
Neurol Res ; : 1-9, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39011891

RESUMO

OBJECTIVE: We aimed to explore the influence of ferroptosis on an oxygen-glucose deprivation/reoxygenation (OGD/R) model in primary rat microglia. METHODS: Primary microglia were extracted from rats and cultured in vitro. The cells were subjected to a hypoxic environment for 6 h in a glucose-free medium, and then re-oxygenated for 24 h in DMEM/F12. Rat microglia were pretreated with the ferroptosis activator erastin and the ferroptosis inhibitor ferrostatin 1 for 24 h, followed by detection of cell cycle progression and apoptosis by flow cytometry. Intracellular total iron levels were measured. In addition, the relative levels of reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD) were determined using enzyme-linked immunosorbent assay. The protein levels of 15-lox2, GPX4, SLC7A11, ACSL4, and TFR1 were examined by western blotting. RESULTS: Compared with rat microglia subjected to OGD/R, pretreatment with erastin did not influence cell apoptosis but significantly enhanced total iron levels, MDA, and ROS levels, whereas it reduced SOD levels. Moreover, it upregulated ACSL4, TFR1, and 15-lox2 and downregulated GPX4 and SLC7A11. Pretreatment with ferrostatin 1 significantly inhibited cell apoptosis and cell cycle arrest in the G0/G1 phase. It significantly reduced total iron levels, MDA, and ROS levels and enhanced SOD levels, which also downregulated ACSL4, TFR1, and 15-lox2, and upregulated GPX4 and SLC7A11. CONCLUSION: Our study showed that inhibition of ferroptosis is favorable against potential OGD/R-induced damage in rat microglia.

5.
FEBS Lett ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39010325

RESUMO

Retinitis pigmentosa (RP) is an inherited eye disease that causes progressive vision loss. Microglial activation and inflammation play essential roles in photoreceptor degeneration in RP, although the underlying mechanisms remain unclear. Here, we examined the progressive degeneration of photoreceptors in rd1 mice, a mouse model of RP. We investigated the molecular changes in various retinal cells in rd1 mice using single-cell RNA sequencing and found that potentiation of JNK signaling is associated with photoreceptor degeneration in RP. Moreover, inflammation-related molecules, which function downstream of JNK, are elevated in RP. Furthermore, inhibiting JNK alleviates microglial activation and rescues photoreceptor degeneration in rd1 mice. Thus, our findings suggest that targeting JNK is a promising approach for slowing RP progression.

6.
Alzheimers Dement ; 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38973166

RESUMO

INTRODUCTION: More robust non-human primate models of Alzheimer's disease (AD) will provide new opportunities to better understand the pathogenesis and progression of AD. METHODS: We designed a CRISPR/Cas9 system to achieve precise genomic deletion of exon 9 in cynomolgus monkeys using two guide RNAs targeting the 3' and 5' intron sequences of PSEN1 exon 9. We performed biochemical, transcriptome, proteome, and biomarker analyses to characterize the cellular and molecular dysregulations of this non-human primate model. RESULTS: We observed early changes of AD-related pathological proteins (cerebrospinal fluid Aß42 and phosphorylated tau) in PSEN1 mutant (ie, PSEN1-ΔE9) monkeys. Blood transcriptome and proteome profiling revealed early changes in inflammatory and immune molecules in juvenile PSEN1-ΔE9 cynomolgus monkeys. DISCUSSION: PSEN1 mutant cynomolgus monkeys recapitulate AD-related pathological protein changes, and reveal early alterations in blood immune signaling. Thus, this model might mimic AD-associated pathogenesis and has potential utility for developing early diagnostic and therapeutic interventions. HIGHLIGHTS: A dual-guide CRISPR/Cas9 system successfully mimics AD PSEN1-ΔE9 mutation by genomic excision of exon 9. PSEN1 mutant cynomolgus monkey-derived fibroblasts exhibit disrupted PSEN1 endoproteolysis and increased Aß secretion. Blood transcriptome and proteome profiling implicate early inflammatory and immune molecular dysregulation in juvenile PSEN1 mutant cynomolgus monkeys. Cerebrospinal fluid from juvenile PSEN1 mutant monkeys recapitulates early changes of AD-related pathological proteins (increased Aß42 and phosphorylated tau).

7.
aBIOTECH ; 5(2): 247-261, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38974861

RESUMO

Genome editing holds great promise for the molecular breeding of plants, yet its application is hindered by the shortage of simple and effective means of delivering genome editing reagents into plants. Conventional plant transformation-based methods for delivery of genome editing reagents into plants often involve prolonged tissue culture, a labor-intensive and technically challenging process for many elite crop cultivars. In this review, we describe various virus-based methods that have been employed to deliver genome editing reagents, including components of the CRISPR/Cas machinery and donor DNA for precision editing in plants. We update the progress in these methods with recent successful examples of genome editing achieved through virus-based delivery in different plant species, highlight the advantages and limitations of these delivery approaches, and discuss the remaining challenges.

8.
Int J Mol Sci ; 25(11)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38891991

RESUMO

The testes serve as the primary source of androgens and the site of spermatogenesis, with their development and function governed by hormonal actions via endocrine and paracrine pathways. Male fertility hinges on the availability of testosterone, a cornerstone of spermatogenesis, while follicle-stimulating hormone (FSH) signaling is indispensable for the proliferation, differentiation, and proper functioning of Sertoli and germ cells. This review covers the research on how androgens, FSH, and other hormones support processes crucial for male fertility in the testis and reproductive tract. These hormones are regulated by the hypothalamic-pituitary-gonad (HPG) axis, which is either quiescent or activated at different stages of the life course, and the regulation of the axis is crucial for the development and normal function of the male reproductive system. Hormonal imbalances, whether due to genetic predispositions or environmental influences, leading to hypogonadism or hypergonadism, can precipitate reproductive disorders. Investigating the regulatory network and molecular mechanisms involved in testicular development and spermatogenesis is instrumental in developing new therapeutic methods, drugs, and male hormonal contraceptives.


Assuntos
Espermatogênese , Testículo , Humanos , Masculino , Testículo/metabolismo , Testículo/crescimento & desenvolvimento , Animais , Hormônio Foliculoestimulante/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Androgênios/metabolismo , Testosterona/metabolismo
9.
BMC Urol ; 24(1): 113, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807082

RESUMO

BACKGROUND: Hemorrhage is a common complication of nephrostomy and percutaneous nephrolithotripsy, and it is caused by surgical factors. Here we report a rare case of hemorrhage caused by sepsis-related coagulation dysfunction. CASE PRESENTATION: A 72-years-old male patient with bilateral ureteral calculi accompanied by hydronephrosis and renal insufficiency developed sepsis and hemorrhage on the third day after bilateral nephrostomy. After vascular injury was excluded by DSA, the hemorrhage was considered to be sepsis-associated coagulopathy(SAC/SIC), finally the patient recovered well after active symptomatic treatment. CONCLUSIONS: In patients with sepsis and hemorrhage, SAC/SIC cannot be excluded even if coagulation function is slightly abnormal after surgical factors are excluded. For urologists who may encounter similar cases in their general urology practice, it is important to be aware of these unusual causes of hemorrhage.


Assuntos
Transtornos da Coagulação Sanguínea , Nefrostomia Percutânea , Sepse , Humanos , Masculino , Idoso , Sepse/etiologia , Nefrostomia Percutânea/efeitos adversos , Transtornos da Coagulação Sanguínea/etiologia , Hemorragia Pós-Operatória/etiologia
10.
Cardiovasc Diabetol ; 23(1): 172, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755609

RESUMO

BACKGROUND: Insulin resistance (IR) is linked to both the complexity of coronary artery lesions and the prognosis of acute coronary syndrome (ACS). However, the precise extent of this correlation and its impact on adverse cardiovascular outcomes in ACS patients remain unclear. Therefore, this study aims to investigate the intricate relationship between IR, coronary artery lesion complexity, and the prognosis of ACS through a cohort design analysis. METHOD: A total of 986 patients with ACS who underwent percutaneous coronary intervention (PCI) were included in this analysis. IR was assessed using the triglyceride-glucose (TyG) index, while coronary artery lesion complexity was evaluated using the SYNTAX score. Pearson's correlation coefficients were utilized to analyze the correlations between variables. The association of the TyG index and SYNTAX score with major adverse cardiovascular events (MACEs) in ACS was investigated using the Kaplan-Meier method, restricted cubic splines (RCS), and adjusted Cox regression. Additionally, a novel 2-stage regression method for survival data was employed in mediation analysis to explore the mediating impact of the SYNTAX score on the association between the TyG index and adverse cardiovascular outcomes, including MACEs and unplanned revascularization. RESULTS: During a median follow-up of 30.72 months, 167 cases of MACEs were documented, including 66 all-cause deaths (6.69%), 26 nonfatal myocardial infarctions (MIs) (2.64%), and 99 unplanned revascularizations (10.04%). The incidence of MACEs, all-cause death, and unplanned revascularization increased with elevated TyG index and SYNTAX score. Both the TyG index (non-linear, P = 0.119) and SYNTAX score (non-linear, P = 0.004) displayed a positive dose-response relationship with MACEs, as illustrated by the RCS curve. Following adjustment for multiple factors, both the TyG index and SYNTAX score emerged as significant predictors of MACEs across the total population and various subgroups. Mediation analysis indicated that the SYNTAX score mediated 25.03%, 18.00%, 14.93%, and 11.53% of the correlation between the TyG index and MACEs in different adjusted models, respectively. Similar mediating effects were observed when endpoint was defined as unplanned revascularization. CONCLUSION: Elevated baseline TyG index and SYNTAX score were associated with a higher risk of MACEs in ACS. Furthermore, the SYNTAX score partially mediated the relationship between the TyG index and adverse cardiovascular outcomes.


Assuntos
Síndrome Coronariana Aguda , Biomarcadores , Glicemia , Doença da Artéria Coronariana , Resistência à Insulina , Intervenção Coronária Percutânea , Humanos , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/mortalidade , Síndrome Coronariana Aguda/terapia , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Glicemia/metabolismo , Fatores de Tempo , Biomarcadores/sangue , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/terapia , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico , Triglicerídeos/sangue , Estudos Retrospectivos , Valor Preditivo dos Testes
11.
Int J Rheum Dis ; 27(5): e15165, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38769820

RESUMO

OBJECTIVE: To compare the clinical efficacy of febuxostat combined with a low-purine diet versus allopurinol combined with a low-purine diet in the treatment of gout. METHODS: In this prospective controlled trial, 98 gout patients admitted to our hospital from February 2021 to December 2022 were enrolled as study subjects. Patients were randomly assigned to the study group (febuxostat combined with a low-purine diet) and the control group (allopurinol combined with a low-purine diet), with 49 patients in each group. The therapeutic effect was evaluated based on joint function and serum uric acid levels after treatment, and classified into three levels: markedly effective, effective, and ineffective. The levels of inflammatory factors, including tumor necrosis factor-a (TNF-a), cytokine interleukin-1beta (IL-1ß), and interleukin (IL)-18 (IL-18), were collected. The Numeric Rating Scale (NRS) was used to assess the degree of pain in patients. Clinical indicators before and 6 months after treatment were compared between the two groups. RESULTS: There was no statistically significant difference in age and gender between the two groups. After 6 months of treatment, the effective rate in the study group (48 cases, 97.96%) was higher than that in the control group (42 cases, 85.71%), with a statistically significant difference (p = .027). At the same time, the study group had significantly lower levels of serum uric acid (162.39 µmol/L ± 17.23 µmol/L vs. S198.32 µmol/L ± 18.34 µmol/L, p < .001), creatinine (87.39 mmol/L ± 9.76 mmol/L vs. 92.18 mmol/L ± 9.27 mmol/L, p = .014), total cholesterol (3.65 mmol/L ± 0.65 mmol/L vs. 4.76 mmol/L ± 0.73 mmol/L, p < .001), and triglycerides (1.76 mmol/L ± 0.32 mmol/L vs. 2.28 mmol/L ± 0.41 mmol/L, p < .001) compared to the control group, with statistically significant differences (p < .05). After treatment, the levels of inflammatory factors and degree of pain in the study group were significantly lower than those in the control group (all p < .05). During the treatment process, the incidence of adverse reactions in the study group (2 cases, 4.08%) was lower than that in the control group (9 cases, 18.37%), with a statistically significant difference (p = .025). CONCLUSION: Febuxostat combined with a low-purine diet can reduce inflammatory factors and alleviate the degree of pain in gout patients, significantly improving their clinical symptoms.


Assuntos
Alopurinol , Febuxostat , Supressores da Gota , Gota , Ácido Úrico , Humanos , Febuxostat/uso terapêutico , Febuxostat/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Alopurinol/uso terapêutico , Gota/tratamento farmacológico , Gota/sangue , Gota/diagnóstico , Supressores da Gota/uso terapêutico , Supressores da Gota/efeitos adversos , Estudos Prospectivos , Resultado do Tratamento , Ácido Úrico/sangue , Idoso , Purinas/uso terapêutico , Biomarcadores/sangue , Terapia Combinada , Fatores de Tempo , Adulto , Mediadores da Inflamação/sangue
12.
Biomol Biomed ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38747892

RESUMO

Dysregulation of glycolysis is frequently linked to aggressive tumor activity in colorectal cancer (CRC). Although serine peptidase inhibitor, Kazal type 4 (SPINK4) has been linked to CRC, its exact linkage to glycolytic processes and gene expression remains unclear. Differentially expressed genes (DEGs) were screened from two CRC-related datasets (GSE32323 and GSE141174), followed by expression and prognostic analysis of SPINK4. In vitro techniques such as flow cytometry, western blotting, transwell assay, and quantitative real-time polymerase chain reaction (qRT-PCR) were used to assess SPINK4 expression in CRC cells. Its effects on apoptosis, glycolysis, and the cell cycle were also investigated. Finally, the impact of SPINK4 overexpression on tumor development was assessed using a xenograft model, while histological and immunohistochemical analyses characterized SPINK4 expression patterns in CRC tissues. SPINK4 expression was downregulated in CRC, correlating with poor patient prognosis. In vitro assays confirmed that overexpression of SPINK4 reduced CRC cell proliferation, invasion, and migration, while its knockdown promoted these processes and caused G1 arrest. SPINK4 also regulated apoptosis by altering caspase activation and Bcl-2 expression. Besides, SPINK4 overexpression altered glycolytic activity, reduced 2-Deoxy-D-glucose (2-DG) absorption, and controlled critical glycolytic enzymes, resulting in alterations in metabolic pathways, whereas SPINK4 knockdown reversed this effect. SPINK4 overexpression significantly reduced tumor volume in vivo, indicating its inhibitory role in carcinogenesis. Moreover, high expression of SPINK4, hexokinase 2 (HK2), glucose transporter 1 (GLUT1), lactate dehydrogenase A (LDHA), and pyruvate kinase M2 (PKM2) was observed in CRC tissues. As a key inhibitor of glycolytic metabolism in CRC, SPINK4 promises metabolic intervention in CRC therapy due to its impact on tumor growth and cell proliferation.

13.
Acta Pharm Sin B ; 14(5): 2177-2193, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38799630

RESUMO

Mornaphthoate E (MPE) is a prenylated naphthoic acid methyl ester isolated from the roots of a famous Chinese medicinal plant Morinda officinalis and shows remarkable cytotoxicity against several human tumor cell lines. In the current project, the first total synthesis of (±)-MPE was achieved in seven steps and 5.6% overall yield. Then the in vitro anti-tumor activity of MPE was first assessed for both enantiomers in two breast cancer cells, with the levoisomer exerting slightly better potency. The in vivo anti-tumor effect was further verified by applying the racemate in an orthotopic autograft mouse model. Notably, MPE exerted promising anti-metastasis activity both in vitro and in vivo and showed no obvious toxicity on mice at the therapeutic dosage. Mechanistic investigations demonstrated that MPE acted as a tubulin polymerization stabilizer and disturbed the dynamic equilibrium of microtubules via regulating PI3K/Akt signaling. In conclusion, our work has provided a new chemical template for the future design and development of next-generation tubulin-targeting chemotherapies.

14.
Heliyon ; 10(9): e30418, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38807610

RESUMO

Objective: To explore the preventive effect of electroacupuncture pretreatment on stroke in rats by inhibiting ferroptosis and oxidative stress. Methods: Rats were randomly assigned to the sham, middle cerebral artery occlusion/reperfusion (MCAO/R), MCAO/R + EP, MCAO/R + EP + erastin, and MCAO/R + EP + ferrostatin 1 groups. Daily electroacupuncture was performed 2 weeks before establishing the MCAO/R model utilizing the modified Zea Longa suture method. Rats were sacrificed 1 day after reperfusion, and brain tissues were collected. They were prepared for hematoxylin and eosin staining, prussian blue staining, transmission electron microscope. Measurement of total iron levels using a commercial kit, detection of malondialdehyde (MDA) and superoxide dismutase (SOD) levels by ELISA, and examination of 15-lox2, GPX4, SLC7A11, ACSL4, and TFR1 by western blotting. Results: Compared with sham rats, cerebral infarction size was dramatically larger in MCAO/R rats. Moreover, the MCAO/R group displayed damaged mitochondria with a disarranged structure of cristae; free iron, total iron levels, and oxidative stress were significantly higher. Cerebral pathological lesions, oxidative stress, total iron levels, and protein levels of ACSL4, TFR1, and 15-lox2 were significantly reduced in the MCAO/R + EP and MCAO/R + EP + ferrostatin 1 groups, while the protective effect of electroacupuncture pretreatment on cerebral ischemia-reperfusion injury was inhibited by treatment with the ferroptosis activator erastin. Conclusion: Electroacupuncture pretreatment can protect rats from cerebral ischemia-reperfusion injury by reducing the area of cerebral infarction and inhibiting ferroptosis and oxidative stress.

15.
Sci Rep ; 14(1): 11630, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773115

RESUMO

The Jishishan Ms 6.2 earthquake occurred at 23:59 on December 18, 2023 in Gansu Province, China. We conducted a field survey to assess the hazards and damages caused by the earthquake and its associated geo-activities. Subsequently, we organized a seminar to discuss the possible causes of the destruction of a prehistoric site-Lajia Settlement-dated back to four thousand years B.P. and located only several kilometers away from the epicenter of the Jishishan earthquake. The Jishishan earthquake was unique for its hazard and disaster process, which featured ground shaking and a series of complex geological and geomorphological activities: sediment and soil spray piles, liquefaction, collapse, landslide, and mudflow along water channels. We define this phenomenon as the Jishishan earthquake ripple hazard (JERH). The most recent evidence from the JERH suggests that a prehistoric earthquake similar to the JERH, instead of riverine floods or earthquake-induced landslide dam outburst flood, as previously hypothesized, destroyed the Lajia Settlement.

16.
Water Res ; 256: 121582, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38608621

RESUMO

Ion-adsorption rare earth element (REE) deposits distributed in the subtropics provide a rich global source of REEs, but in situ injection of REEs extractant into the mine can result in leachate being leaked into the surrounding groundwater systems. Due to the lack of understanding of REE speciation distribution, particularly colloidal characteristics in a mining area, the risks of REEs migration caused by in situ leaching of ion-adsorption REE deposits has not been concerned. Here, ultrafiltration and asymmetric flow field-flow fractionation coupled with inductively coupled plasma mass spectrometry (AF4-ICP-MS) were integrated to characterize the size and composition of REEs in leachate and groundwater from mining catchments in South China. Results show that REEs were associated with four fractions: 1) the <1 kDa fraction including dissolved REEs; 2) the 1 - 100 kDa nano-colloidal fraction containing organic compounds; 3) the 100 kDa - 220 nm fine colloids including organic-mineral (Fe, Mn and Al (oxy)hydroxides and clay minerals); 4) the >220 nm coarse colloids and acid soluble particles (ASPs) comprising minerals. Influenced by the ion exchange effect of in situ leaching, REEs in leachate were mostly dissolved (79 %). The pH of the groundwater far from the mine site was increased (5.8 - 7.3), the fine organic-mineral colloids (46 % - 80 %) were the main vectors of transport for REEs. Further analysis by AF4 revealed that the fine colloids can be divided into mineral-rich (F1, 100 kDa - 120 nm) and organic matter-rich (F2, 120 - 220 nm) populations. The main colloids associated with REEs shifted from F1 (64 % ∼ 76 %) to F2 (50 % ∼ 52 %) away from the mining area. For F1 and F2, the metal/C molar ratio decreased away from the mining area and middle to heavy REE enrichment was presented. According to the REE fractionation, organic matter was the predominant component capable of binding REEs in fine colloids. Overall, our results indicate that REEs in the groundwater system shifted from the dissolved to the colloidal phase in a catchment affected by in situ leaching, and organic-mineral colloids play an important role in facilitating the migration of REEs.


Assuntos
Coloides , Água Subterrânea , Metais Terras Raras , Minerais , Mineração , Poluentes Químicos da Água , Água Subterrânea/química , Coloides/química , China , Minerais/química , Adsorção
17.
Nat Commun ; 15(1): 3015, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589344

RESUMO

Many experimental and computational efforts have sought to understand DNA origami folding, but the time and length scales of this process pose significant challenges. Here, we present a mesoscopic model that uses a switchable force field to capture the behavior of single- and double-stranded DNA motifs and transitions between them, allowing us to simulate the folding of DNA origami up to several kilobases in size. Brownian dynamics simulations of small structures reveal a hierarchical folding process involving zipping into a partially folded precursor followed by crystallization into the final structure. We elucidate the effects of various design choices on folding order and kinetics. Larger structures are found to exhibit heterogeneous staple incorporation kinetics and frequent trapping in metastable states, as opposed to more accessible structures which exhibit first-order kinetics and virtually defect-free folding. This model opens an avenue to better understand and design DNA nanostructures for improved yield and folding performance.


Assuntos
Nanoestruturas , Nanotecnologia , Conformação de Ácido Nucleico , DNA/química , Nanoestruturas/química , Cinética
18.
Nat Commun ; 15(1): 3563, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38670969

RESUMO

Synthetic glucocorticoids (GC), such as dexamethasone, are extensively used to treat chronic inflammation and autoimmune disorders. However, long-term treatments are limited by various side effects, including muscle atrophy. GC activities are mediated by the glucocorticoid receptor (GR), that regulates target gene expression in various tissues in association with cell-specific co-regulators. Here we show that GR and the lysine-specific demethylase 1 (LSD1) interact in myofibers of male mice, and that LSD1 connects GR-bound enhancers with NRF1-associated promoters to stimulate target gene expression. In addition, we unravel that LSD1 demethylase activity is required for triggering starvation- and dexamethasone-induced skeletal muscle proteolysis in collaboration with GR. Importantly, inhibition of LSD1 circumvents muscle wasting induced by pharmacological levels of dexamethasone, without affecting their anti-inflammatory activities. Thus, our findings provide mechanistic insights into the muscle-specific GC activities, and highlight the therapeutic potential of targeting GR co-regulators to limit corticotherapy-induced side effects.


Assuntos
Dexametasona , Glucocorticoides , Histona Desmetilases , Músculo Esquelético , Atrofia Muscular , Receptores de Glucocorticoides , Animais , Masculino , Histona Desmetilases/metabolismo , Histona Desmetilases/antagonistas & inibidores , Histona Desmetilases/genética , Glucocorticoides/farmacologia , Dexametasona/farmacologia , Receptores de Glucocorticoides/metabolismo , Camundongos , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Atrofia Muscular/tratamento farmacológico , Músculo Esquelético/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Camundongos Endogâmicos C57BL , Regulação da Expressão Gênica/efeitos dos fármacos
19.
J Extracell Vesicles ; 13(4): e12425, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38594791

RESUMO

Heterotopic ossification (HO) comprises the abnormal formation of ectopic bone in extraskeletal soft tissue. The factors that initiate HO remain elusive. Herein, we found that calcified apoptotic vesicles (apoVs) led to increased calcification and stiffness of tendon extracellular matrix (ECM), which initiated M2 macrophage polarization and HO progression. Specifically, single-cell transcriptome analyses of different stages of HO revealed that calcified apoVs were primarily secreted by a PROCR+ fibroblast population. In addition, calcified apoVs enriched calcium by annexin channels, absorbed to collagen I via electrostatic interaction, and aggregated to produce calcifying nodules in the ECM, leading to tendon calcification and stiffening. More importantly, apoV-releasing inhibition or macrophage deletion both successfully reversed HO development. Thus, we are the first to identify calcified apoVs from PROCR+ fibroblasts as the initiating factor of HO, and might serve as the therapeutic target for inhibiting pathological calcification.


Assuntos
Vesículas Extracelulares , Ossificação Heterotópica , Humanos , Receptor de Proteína C Endotelial , Vesículas Extracelulares/patologia , Ossificação Heterotópica/patologia , Ossificação Heterotópica/terapia , Matriz Extracelular , Fibroblastos
20.
Transl Cancer Res ; 13(3): 1493-1507, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38617511

RESUMO

Background: Colorectal cancer (CRC) poses a significant challenge in digestive system diseases, and emerging evidence underscores the critical role of zinc metabolism in its progression. This study aimed to investigate the clinical implications of genes at the intersection of zinc metabolism and CRC. Methods: We downloaded CRC prognosis-related genes and zinc metabolism-related genes from public databases. Then, the overlapping genes were screened out, and bioinformatics analysis was performed to obtain the hub gene associated with CRC prognosis. Subsequently, in vitro assays were carried out to investigate the expression of this hub gene and its exact mechanism between zinc metabolism and CRC. Results: HAMP was identified as the hub CRC prognostic gene from overlapping zinc metabolism-related and CRC prognostic genes. In vitro analysis showed HAMP was over-expressed in CRC, and its knockdown inhibited RKO and HCT-116 cell invasion and migration significantly. ZnSO4 induced HAMP up-regulation to promote cell proliferation, while TPEN decreased HAMP expression to inhibit cell proliferation. Importantly, we further found that ZnSO4 enhanced SMAD4 expression to augment HAMP promoter activity and promote cell proliferation in CRC. Conclusions: HAMP stands out as an independent prognostic factor in CRC, representing a potential therapeutic target. Its intricate regulation by zinc, particularly through the modulation of SMAD4, unveils a novel avenue for understanding CRC biology. This study provides valuable insights into the interplay between zinc metabolism, HAMP, and CRC, offering promising clinical indicators for CRC patients. The findings present a compelling case for further exploration and development of targeted therapeutic strategies in CRC management.

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