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1.
Mol Neurobiol ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38981960

RESUMO

Hemorrhagic stroke is a global health problem owing to its high morbidity and mortality rates. Nicotinamide riboside is an important precursor of nicotinamide adenine dinucleotide characterized by a high bioavailability, safety profile, and robust effects on many cellular signaling processes. This study aimed to investigate the protective effects of nicotinamide riboside against collagenase-induced hemorrhagic stroke and its underlying mechanisms of action. An intracerebral hemorrhage model was constructed by stereotactically injecting collagenase into the right striatum of adult male Institute for Cancer Research mice. After 30 minutes, nicotinamide riboside was administered via the tail vein. The mice were sacrificed at different time points for assessments. Nicotinamide riboside reduced collagenase-induced hemorrhagic area, significantly reduced cerebral water content and histopathological damage, promoted neurological function recovery, and suppressed reactive oxygen species production and neuroinflammation. Nicotinamide riboside exerts neuroprotective effects against collagenase-induced intracerebral hemorrhage by inhibiting neuroinflammation and oxidative stress.

2.
Int J Gen Med ; 17: 1887-1895, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38736670

RESUMO

Purpose: This study aimed to investigate the alteration trends and overlaps of positive features in benign and malignant thyroid nodules of different sizes based on the Chinese Thyroid Imaging Reporting and Data System (C-TIRADS). Patients and Methods: 1337 patients with 1558 thyroid nodules were retrospectively recruited from November 2021 to December 2023. These nodules were divided into three groups according to maximum diameter: A (≤10 mm), B (10-20 mm), and C (≥20 mm). C-TIRADS positive features were compared between benign and malignant thyroid nodules of different sizes. In addition, the trends of positive features with changes in nodule size among malignant thyroid nodules were analyzed. Results: The incidence of positive features in malignant thyroid nodules was higher than that in benign. As benign nodules grow, the incidence of all positive features showed a linear decreasing trend (Z values were 72.103, 101.081, 17.344, 33.909, and 129.304, P values < 0.001). With the size of malignant thyroid nodules increased, vertical orientation, solid, marked hypoechogenicity, and ill-defined/irregular margins/extrathyroidal extension showed a linear decreasing trend (Z = 148.854, 135.378, 8.590, and 69.239, respectively; P values < 0.05), while suspicious microcalcifications showed a linear increasing trend (Z = 34.699, P<0.001). In terms of overlapping characteristics, group A had a significantly higher overlapping rate than the other two groups, and the overlapping rate of solid indicators remained the highest among all three groups (P < 0.05). Conclusion: Differences in positive features were observed between thyroid nodules of different sizes. Except for suspicious microcalcifications, the incidence of other four positive features decreased with increasing nodule size. In addition, a negative correlation was observed between the overlap rate and nodule size. These results may provide a basis for sonographers to upgrade or downgrade thyroid nodules based on their own experience.

3.
Redox Biol ; 73: 103176, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38705094

RESUMO

Excitotoxicity is a prevalent pathological event in neurodegenerative diseases. The involvement of ferroptosis in the pathogenesis of excitotoxicity remains elusive. Transcriptome analysis has revealed that cytoplasmic reduced nicotinamide adenine dinucleotide phosphate (NADPH) levels are associated with susceptibility to ferroptosis-inducing compounds. Here we show that exogenous NADPH, besides being reductant, interacts with N-myristoyltransferase 2 (NMT2) and upregulates the N-myristoylated ferroptosis suppressor protein 1 (FSP1). NADPH increases membrane-localized FSP1 and strengthens resistance to ferroptosis. Arg-291 of NMT2 is critical for the NADPH-NMT2-FSP1 axis-mediated suppression of ferroptosis. This study suggests that NMT2 plays a pivotal role by bridging NADPH levels and neuronal susceptibility to ferroptosis. We propose a mechanism by which the NADPH regulates N-myristoylation, which has important implications for ferroptosis and disease treatment.


Assuntos
Ferroptose , NADP , Humanos , NADP/metabolismo , Animais , Aciltransferases/metabolismo , Aciltransferases/genética , Camundongos , Processamento de Proteína Pós-Traducional
5.
Angew Chem Int Ed Engl ; 63(28): e202404329, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38683742

RESUMO

A hitherto unknown class of C4-symmetric Caryl-Cß (C3, C8, C13, C18) axially chiral porphyrins has been synthesized and the application of their iridium (Ir) complexes in catalytic asymmetric C(sp3)-H functionalization is documented. Cyclotetramerization of enantioenriched axially chiral 2-hydroxymethyl-3-naphthyl pyrroles under mild acidic conditions affords, after oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), the C4-symmetric α,α,α,α-atropenantiomer as an only isolable diastereomer. Both regioisomeric Ir(Por*)(CO)(Cl) complexes catalyze the carbene C-H insertion reaction affording the same enantiomer, albeit with slight difference in enantioselectivity. With the optimum Ir-complex 3 e, the 2-substituted arylacetic acid derivatives were generated from diazo compounds and cyclohexadiene in excellent yields and enantioselectivities.

6.
World J Psychiatry ; 14(3): 388-397, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38617983

RESUMO

BACKGROUND: Major depressive disorder is a common mental illness among adolescents and is the largest disease burden in this age group. Most adolescent patients with depression have suicidal ideation (SI); however, few studies have focused on the factors related to SI, and effective predictive models are lacking. AIM: To construct a risk prediction model for SI in adolescent depression and provide a reference assessment tool for prevention. METHODS: The data of 150 adolescent patients with depression at the First People's Hospital of Lianyungang from June 2020 to December 2022 were retrospectively analyzed. Based on whether or not they had SI, they were divided into a SI group (n = 91) and a non-SI group (n = 59). The general data and laboratory indices of the two groups were compared. Logistic regression was used to analyze the factors influencing SI in adolescent patients with depression, a nomogram prediction model was constructed based on the analysis results, and internal evaluation was performed. Receiver operating characteristic and calibration curves were used to evaluate the model's efficacy, and the clinical application value was evaluated using decision curve analysis (DCA). RESULTS: There were differences in trauma history, triggers, serum ferritin levels (SF), high-sensitivity C-reactive protein levels (hs-CRP), and high-density lipoprotein (HDL-C) levels between the two groups (P < 0.05). Logistic regression analysis showed that trauma history, predisposing factors, SF, hs-CRP, and HDL-C were factors influencing SI in adolescent patients with depression. The area under the curve of the nomogram prediction model was 0.831 (95%CI: 0.763-0.899), sensitivity was 0.912, and specificity was 0.678. The higher net benefit of the DCA and the average absolute error of the calibration curve were 0.043, indicating that the model had a good fit. CONCLUSION: The nomogram prediction model based on trauma history, triggers, ferritin, serum hs-CRP, and HDL-C levels can effectively predict the risk of SI in adolescent patients with depression.

7.
RSC Adv ; 14(17): 11862-11871, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38623293

RESUMO

Since Na3V2(PO4)3 (NVP) possesses modest volume deformation and three-dimensional ion diffusion channels, it is a potential sodium-ion battery cathode material that has been extensively researched. Nonetheless, NVP still endures the consequences of poor electronic conductivity and low voltage platforms, which need to be further improved. On this basis, a high voltage platform Na3V2(PO4)2F3 was introduced to form a composite with NVP to increase the energy density. In this study, the sol-gel technique was successfully used to synthesize a Na3V2(PO4)2.75F0.75/C (NVPF·3NVP/C) composite cathode material. The citric acid-derived carbon layer was utilized to construct three-dimensional conducting networks to effectively promote ion and electron diffusion. Furthermore, the composites' synergistic effect accelerates the quick ionic migration and improves the kinetic reaction. In particular, NVP as the dominant phase enhanced the structural stability and significantly increased the capacitive contribution. Therefore, at 0.1C, the discharge capacity of the modified NVPF·3NVP/C composite is 120.7 mA h g-1, which is greater than the theoretical discharge capacity of pure NVP (118 mA h g-1). It discharged 110.9 mA h g-1 of reversible capacity even at an elevated multiplicity of 10C, and after 200 cycles, it retained 64.1% of its capacity. Thus, the effort produced an optimized NVPF·3NVP/C composite cathode material that may be used in the sodium ion cathode.

8.
Adv Sci (Weinh) ; 11(25): e2309657, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38654462

RESUMO

Alleviating the decomposition of the electrolyte is of great significance to improving the cycle stability of cathodes, especially for LiCoO2 (LCO), its volumetric energy density can be effectively promoted by increasing the charge cutoff voltage to 4.6 V, thereby supporting the large-scale application of clean energy. However, the rapid decomposition of the electrolyte under 4.6 V conditions not only loses the transport carrier for lithium ion, but also produces HF and insulators that destroy the interface of LCO and increase impedance. In this work, the decomposition of electrolyte is effectively suppressed by changing the adsorption force between LCO interface and EC. Density functional theory illustrates the LCO coated with lower electronegativity elements has a weaker adsorption force with the electrolyte, the adsorption energy between LCO@Mg and EC (0.49 eV) is weaker than that of LCO@Ti (0.73 eV). Meanwhile, based on the results of time of flight secondary ion mass spectrometry, conductivity-atomic force microscopy, in situ differential electrochemical mass spectrometry, soft X-ray absorption spectroscopy, and nuclear magnetic resonance, as the adsorption force increases, the electrolyte decomposes more seriously. This work provides a new perspective on the interaction between electrolyte and the interface of cathode and further improves the understanding of electrolyte decomposition.

9.
ACS Appl Mater Interfaces ; 16(5): 6143-6151, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38270105

RESUMO

V5S8 has received extensive attention in the field of sodium-ion batteries (SIBs) due to its two-dimensional (2D) layered structure, and weak van der Waals forces between V-S accelerate the transport of sodium ions. However, the long-term cycling of V5S8 still suffers from volume expansion and low conductivity. Herein, a hollow nanotube V5S8@C (H-V5S8@C) with improved conductivity was synthesized by a solvothermal method to alleviate cracking caused by volume expansion. Benefiting from the large specific surface area of the hollow nanotube structure and uniform carbon coating, H-V5S8@C exhibits a more active site and enhanced conductivity. Meanwhile, the heterojunction formed by a few residual MoS2 and the outer layer of V5S8 stabilizes the structure and reduces the ion migration barrier with fast Na+ transport. Specifically, the H-V5S8@C anode provides an enhanced rate performance of 270.1 mAh g-1 at 15 A g-1 and high cycling stability of 291.7 mAh g-1 with a retention rate of 90.98% after 300 cycles at 5 A g-1. This work provides a feasible approach for the structural design of 2D layered materials, which can promote the practical application of fast-charging sodium-ion batteries.

10.
Appl Biochem Biotechnol ; 196(3): 1450-1463, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37418127

RESUMO

S-adenosyl-l-methionine (SAM), a vital physiologically active substance in living organisms, is produced by fermentation over Saccharomyces cerevisiae. The main limitation in SAM production was the low biosynthesis ability of SAM in S. cerevisiae. The aim of this work is to breed an SAM-overproducing mutant through UV mutagenesis coupled with high-throughput selection. Firstly, a high-throughput screening method by rapid identification of positive colonies was conducted. White colonies on YND medium were selected as positive strains. Then, nystatin/sinefungin was chosen as a resistant agent in directed mutagenesis. After several cycles of mutagenesis, a stable mutant 616-19-5 was successfully obtained and exhibited higher SAM production (0.41 g/L vs 1.39 g/L). Furthermore, the transcript levels of the genes SAM2, ADO1, and CHO2 involved in SAM biosynthesis increased, while ergosterol biosynthesis genes in mutant 616-19-5 significantly decreased. Finally, building on the above work, S. cerevisiae 616-19-5 could produce 10.92 ± 0.2 g/L SAM in a 5-L fermenter after 96 h of fermentation, showing a 2.02-fold increase in the product yield compared with the parent strain. Paving the way of breeding SAM-overproducing strain has improved the good basis for SAM industrial production.


Assuntos
Metionina , S-Adenosilmetionina , Saccharomyces cerevisiae/genética , Ensaios de Triagem em Larga Escala , Melhoramento Vegetal , Racemetionina
12.
Small Methods ; : e2301199, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38126678

RESUMO

Silicon (Si) is recognized as a promising anode material for next-generation anodes due to its high capacity. However, large volume expansion and active particle pulverization during cycling rapidly deteriorate the battery performance. The relationship between Si anode particle size and particle pulverization, and the structure evolution of Si particles during cycling is not well understood. In this study, a quantitative, time-resolved "operando" small angle X-ray scattering (SAXS) investigation into the morphological change of unwrapped and reduced graphene oxide (rGO) wrapped Si nanoparticles (Si@rGO) is conducted with respect to the operating voltage. The results provide a clear picture of Si particle size change and the role of nonrigid rGO in mitigating Si volume expansion and pulverization. Further, this study demonstrates the advantage of "operando" SAXS in electrochemical environments as compared to other approaches.

13.
Shock ; 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37878471

RESUMO

BACKGROUND: Recent studies have shown that ferroptosis is involved in the evolution of acute lung injury (ALI), a serious respiratory pathological process leading to death. However, the regulatory mechanisms underlying ferroptosis in ALI remain largely unknown. The current study analyzed and identified a ferroptosis-related gene signature for ALI. METHODS: Key genes associated with ferroptosis in ALI were identified by bioinformatics analysis. GSE104214, GSE18341, and GSE17355 datasets were downloaded from the Gene Expression Omnibus database. The signature genes were screened by least absolute shrinkage and selection operator (LASSO) regression, and the key genes of ALI were screened by weighted correlation network analysis (WGCNA), followed by immune infiltration analysis and functional enrichment analysis. In addition, mRNA expression of key genes in the lungs of mice with hemorrhagic shock and sepsis was verified. RESULTS: A total of 2132 differential genes were identified by various analyses, and nine characteristic genes were detected using Lasso regression. We intersected nine signature genes with WGCNA module genes and finally determined four key genes (PROK2, IL6, TNF, SLC7A11). All four key genes were closely correlated with immune cells and regulatory genes of ALI, and the expression of the four genes was significantly different in the lung tissues of hemorrhagic shock and sepsis models. Besides, the ferroptosis related molecules GPX4 and ACSL4 showed remarkable difference in these models. CONCLUSION: These results indicate that PROK2, IL6, TNF, SLC7A11 may be key regulatory targets of ferroptosis during ALI. This study proved that ferroptosis is a common pathophysiological process in three ALI models.

14.
Front Genet ; 14: 1237821, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37829277

RESUMO

Background: Noonan syndrome (NS) is characterized by typical facial features, short stature, congenital heart defects and other comorbidities. Lymphedema and chylous pleural effusions are also common in NS, but protein-losing enteropathy (PLE) is rarely reported. Case presentation: We present the case of a 19-year-old Chinese woman presenting with PLE. Small intestine biopsy showed obvious expansion of lymphatic vessels. The gene mutation results of the patient indicated a c.184T>G missense mutation (p.Tyr62Asp) in the PTPN11 gene (NM_002834.3). Conclusion: NS accompanied by PLE is not common, but hypoproteinemia attributable to PLE may be more common in patients with NS than previously thought. It remains uncertain whether mutation of the PTPN11 gene is related to PLE, indicating that further research is needed.

15.
Chem Commun (Camb) ; 59(72): 10745-10748, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37581907

RESUMO

We propose a practical strategy to design a series of heavy-atom-free synergistic phototherapy agents (CSQs) with both photodynamic therapy (PDT) and photothermal therapy (PTT) under NIR wavelength excitation by simply replacing the indole salt of xanthene Changsha (CS) with quinoline salt.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Quinolinas , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fototerapia , Cloreto de Sódio , Neoplasias/tratamento farmacológico , Quinolinas/farmacologia
16.
BMC Surg ; 23(1): 222, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37559107

RESUMO

BACKGROUND: Delayed gastric emptying (DGE) remains one of the major complications after pancreaticoduodenectomy (PD), with discrepant reports of its contributing factors. This study aimed to develop a nomogram to identify potential predictors and predict the probability of DGE after PD. METHODS: This retrospective study enrolled 422 consecutive patients who underwent PD from January 2019 to December 2021 at our institution. The LASSO algorithm and multivariate logistic regression were performed to identify independent risk and protective factors associated with clinically relevant delayed gastric emptying (CR-DGE). A nomogram was established based on the selected variables. Then, the calibration curve, ROC curve, decision curve analysis (DCA), and clinical impact curve (CIC) were applied to evaluate the predictive performance of our model. Finally, an independent cohort of 45 consecutive patients from January 2022 to March 2022 was enrolled to further validate the nomogram. RESULTS: Among 422 patients, CR-DGE occurred in 94 patients (22.2%). A previous history of chronic gastropathy, intraoperative plasma transfusion ≥ 400 ml, end-to-side gastrointestinal anastomosis, intra-abdominal infection, incisional infection, and clinically relevant postoperative pancreatic fistula (CR-POPF) were identified as risk predictors. Minimally invasive pancreaticoduodenectomy (MIPD) was demonstrated to be a protective predictor of CR-DGE. The areas under the curve (AUCs) were 0.768 (95% CI, 0.706-0.830) in the development cohort, 0.766 (95% CI, 0.671-0.861) in the validation cohort, and 0.787 (95% CI, 0.633-0.940) in the independent cohort. Then, we built a simplified scale based on our nomogram for risk stratification. CONCLUSIONS: Our study identified seven predictors and constructed a validated nomogram that effectively predicted CR-DGE for patients who underwent PD.


Assuntos
Gastroparesia , Pancreaticoduodenectomia , Humanos , Pancreaticoduodenectomia/efeitos adversos , Gastroparesia/epidemiologia , Gastroparesia/etiologia , Estudos Retrospectivos , Transfusão de Componentes Sanguíneos/efeitos adversos , Fatores de Risco , Plasma , Anastomose Cirúrgica/efeitos adversos , Medição de Risco , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Esvaziamento Gástrico
17.
Chem Commun (Camb) ; 59(68): 10295-10298, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37540031

RESUMO

Bismuth(III) iodide perovskites have attracted great attention as lead-free hybrid semiconductors, but they mainly show zero- and one-dimensional structures. Herein, we report the first two-dimensional chiral perovskite-like bismuth(III) iodide hybrid [(S)-3-aminopyrrolidinium I]2Bi2/3I4 (1) with a high phase transition temperature of 408.8 K, higher than most of the reported chiral lead-free hybrid semiconductors.

18.
Quant Imaging Med Surg ; 13(6): 3902-3914, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37284072

RESUMO

Background: Contrast-enhanced ultrasound (CEUS) has proven valuable in diagnosing benign and malignant pancreatic diseases, but its value in evaluating hepatic metastasis remains to be further explored. This study investigated the relationship between CEUS features of pancreatic ductal adenocarcinoma (PDAC) and concomitant or recurrent liver metastases after treatment. Methods: This retrospective study included 133 participants with PDAC who were diagnosed with pancreatic lesions with CEUS at Peking Union Medical College Hospital from January 2017 to November 2020. According to the CEUS classification methods in our center, all the pancreatic lesions were classified as either with rich or poor blood supply. Additionally, quantitative ultrasonographic parameters were measured in the center and periphery of all pancreatic lesions. CEUS modes and parameters of the different hepatic metastasis groups were compared. The diagnostic performance of CEUS was calculated for diagnosing synchronous and metachronous hepatic metastasis. Results: The proportions of rich blood supply and poor blood supply were 46% (32/69) and 54% (37/69), respectively, in the no hepatic metastasis group; 42% (14/33) and 58% (19/33), respectively, in the metachronous hepatic metastasis (MHM) group; and 19% (6/31) and 81% (25/31), respectively, in the synchronous hepatic metastasis (SHM) group. The wash-in slope ratio (WIS ratio) between the center of the lesion and around the lesion and peak intensity ratio (PI ratio) between the center of the lesion and around the lesion had higher values in the negative hepatic metastasis group (P<0.05). In predicting synchronous and metachronous hepatic metastasis, the WIS ratio had the best diagnostic performance. The sensitivity (SEN), specificity (SPE), accuracy (ACC), positive predictive value (PPV), and negative predictive value (NPV) were 81.8%, 95.7%, 91.2%, 90.0%, and 91.7%, respectively, for MHM; and 87.1%, 95.7%, 93.0%, 90.0%, and 94.3%, respectively, for SHM. Conclusions: CEUS would be helpful in image surveillance for synchronous or metachronous hepatic metastasis of PDAC.

19.
JACS Au ; 3(4): 1196-1204, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37124294

RESUMO

Ferroelectric materials are a special type of polar substances, including solids or liquid crystals. However, obtaining a material to be ferroelectric in both its solid crystal (SC) and liquid crystal (LC) phases is a great challenge. Moreover, although cholesteric LCs inherently possess the advantage of high fluidity, their ferroelectricity remains unknown. Here, through the reasonable H/F substitution on the fourth position of the phenyl group of the parent nonferroelectric dihydrocholesteryl benzoate, we designed ferroelectric dihydrocholesteryl 4-fluorobenzoate (4-F-BDC), which shows ferroelectricity in both SC and cholesteric LC phases. The fluorination induces a lower symmetric polar P1 space group and a new solid-to-solid phase transition in 4-F-BDC. Beneficial from fluorination, the SC and cholesteric LC phases of 4-F-BDC show clear ferroelectricity, as confirmed by well-shaped polarization-voltage hysteresis loops. The dual ferroelectricity in both SC and cholesteric LC phases of a single material was rarely found. This work offers a viable case for the exploration of the interplay between ferroelectric SC and LC phases and provides an efficient approach for designing ferroelectrics with dual ferroelectricity and cholesteric ferroelectric liquid crystals.

20.
Adv Mater ; 35(33): e2302436, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37202898

RESUMO

Ferroelectricity has been separately found in numerous solid and liquid crystal materials since its first discovery in 1920. However, a single material with biferroelectricity existing in both solid and liquid crystal phases is very rare, and the regulation of biferroelectricity has never been studied. Here, solid-liquid crystal biphasic ferroelectrics, cholestanyl 4-X-benzoate (4X-CB, X = Cl, Br, and I), which exhibits biferroelectricity in both the solid and liquid crystal phases, is presented. It is noted that the ferroelectric liquid crystal phase of 4X-CB is a cholesteric one, distinct from the ordinary chiral smectic ferroelectric liquid crystal phase. Moreover, 4X-CB shows solid-solid and solid-liquid crystal phase transitions, of which the transition temperatures gradually increase from Cl to Br to I substitution. The spontaneous polarization (Ps ) of 4X-CB in both solid and liquid crystal phases can also be regulated by different halogen substitutions, where the 4Br-CB has the optimal Ps because of the larger molecular dipole moment. To the authors' knowledge, 4X-CB is the first ferroelectric with tunable biferroelectricity, which offers a feasible case for the performance optimization of solid-liquid crystal biphasic ferroelectrics.

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