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1.
World J Diabetes ; 15(5): 898-913, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38766436

RESUMO

BACKGROUND: The understanding of bile acid (BA) and unsaturated fatty acid (UFA) profiles, as well as their dysregulation, remains elusive in individuals with type 2 diabetes mellitus (T2DM) coexisting with non-alcoholic fatty liver disease (NAFLD). Investigating these metabolites could offer valuable insights into the pathophy-siology of NAFLD in T2DM. AIM: To identify potential metabolite biomarkers capable of distinguishing between NAFLD and T2DM. METHODS: A training model was developed involving 399 participants, comprising 113 healthy controls (HCs), 134 individuals with T2DM without NAFLD, and 152 individuals with T2DM and NAFLD. External validation encompassed 172 participants. NAFLD patients were divided based on liver fibrosis scores. The analytical approach employed univariate testing, orthogonal partial least squares-discriminant analysis, logistic regression, receiver operating characteristic curve analysis, and decision curve analysis to pinpoint and assess the diagnostic value of serum biomarkers. RESULTS: Compared to HCs, both T2DM and NAFLD groups exhibited diminished levels of specific BAs. In UFAs, particular acids exhibited a positive correlation with NAFLD risk in T2DM, while the ω-6:ω-3 UFA ratio demonstrated a negative correlation. Levels of α-linolenic acid and γ-linolenic acid were linked to significant liver fibrosis in NAFLD. The validation cohort substantiated the predictive efficacy of these biomarkers for assessing NAFLD risk in T2DM patients. CONCLUSION: This study underscores the connection between altered BA and UFA profiles and the presence of NAFLD in individuals with T2DM, proposing their potential as biomarkers in the pathogenesis of NAFLD.

2.
New Phytol ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38708492

RESUMO

In plant species, anthocyanin accumulation is specifically regulated by light signaling. Although the CONSTITUTIVELY PHOTOMORPHOGENIC1/SUPPRESSOR OF PHYA-105 (COP1/SPA) complex is known to control anthocyanin biosynthesis in response to light, the precise mechanism underlying this process remains largely unknown. Here, we report that Increase in BONSAI Methylation 1 (IBM1), a JmjC domain-containing histone demethylase, participates in the regulation of light-induced anthocyanin biosynthesis in Arabidopsis. The expression of IBM1 was induced by high light (HL) stress, and loss-of-function mutations in IBM1 led to accelerated anthocyanin accumulation under HL conditions. We further identified that IBM1 is directly associated with SPA1/3/4 chromatin in vivo to establish a hypomethylation status on H3K9 and DNA non-CG at these loci under HL, thereby releasing their expression. Genetic analysis showed that quadruple mutants of IBM1 and SPA1/3/4 resemble spa134 mutants. Overexpression of SPA1 in ibm1 mutants complements the mutant phenotype. Our results elucidate the significance and mechanism of IBM1 histone demethylase in the epigenetic regulation of anthocyanin biosynthesis in Arabidopsis under HL conditions.

3.
Medicine (Baltimore) ; 103(16): e37850, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640311

RESUMO

BACKGROUND: Isolated ischemic oculomotor nerve palsy as a type of ophthalmic disease is rarely observed in clinical practice. Quality of life is frequently impacted by isolated ischemic oculomotor nerve palsy due to its lack of treatment options and long-term visual impairment. We describe an acupuncture-treated instance of isolated ischemic oculomotor paralysis. METHODS: Acupoints including Jingming (BL 1), Chengqi (ST 1), Cuanzhu (BL 2), and Sizhukong (TE 23) on the right side, and bilateral Fengchi (GB 20), Waiguan (TE 5), Hegu (LI 4), and Zulinqi (GB 41) were selected for needling. Each treatment lasted for 30 minutes, once every other day. Acupuncture treatment was administered for a total of 11 times. RESULTS: Acupuncture is a promising treatment option for isolated ischemic oculomotor nerve palsy. CONCLUSIONS: Ischemic oculomotor nerve paralysis can affect the quality of life of patients. Acupuncture intervention can promote the recovery of the disease is a very effective treatment measure.


Assuntos
Terapia por Acupuntura , Acupuntura , Doenças do Nervo Oculomotor , Humanos , Qualidade de Vida , Pontos de Acupuntura , Doenças do Nervo Oculomotor/etiologia , Doenças do Nervo Oculomotor/terapia
4.
Phys Chem Chem Phys ; 26(15): 11738-11745, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38563831

RESUMO

High-performance sodium-ion batteries (SIBs) require anode materials with high capacity and fast kinetics. Based on first-principles calculations, we propose BC3N2 and BC3N2/graphene (B/G) heterostructure as potential SIB anode materials. The BC3N2 monolayer exhibits intrinsic metallic behavior. In addition, BC3N2 possesses a low Na+ diffusion barrier (0.15 eV), a high storage capacity (777 mA h g-1), a low open-circuit voltage (0.72 V), and a tiny axial expansion (0.36%). Compared with the BC3N2 monolayer, the B/G heterostructure exhibits a lower diffusion barrier of 0.027 eV, suggesting a much faster diffusion. More importantly, although the B/G heterostructure possesses heavier molar weight, its theoretical capacity (689 mA h g-1) is comparable to that of the BC3N2 monolayer. Based on the above-mentioned properties, we hope both the BC3N2 monolayer and the B/G heterostructure would be promising anodes for SIBs.

5.
Gastroenterology ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38631417
6.
Heliyon ; 10(7): e29214, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38601586

RESUMO

Objective: The study established a nomogram based on quantitative parameters of spectral computed tomography (CT) and clinical characteristics, aiming to evaluate its predictive value for preoperative lymphovascular invasion (LVI) in gastric cancer (GC). Methods: From December 2019 to December 2021, 171 patients with pathologically confirmed GC were retrospectively collected with corresponding clinical data and spectral CT quantitative data. Patients were divided into LVI-positive and LVI-negative groups based on their pathological results. The univariate and multivariate logistic regression analyses were used to identify the risk factors and construct a nomogram. The calibration curve and receiver operating characteristic (ROC) curve were adopted to evaluate the predictive accuracy of nomogram. Results: Four clinical characteristics or spectral CT quantitative parameters, including Borrmann classification (P = 0.039), CA724 (P = 0.007), tumor thickness (P = 0.031), and iodine concentration in the venous phase (VIC) (P = 0.004) were identified as independent factors for LVI in GC patients. The nomogram was established based on the four factors, which had a potent predictive accuracy in the training, internal validation and external validation cohorts, with the area under the ROC curve (AUC) of 0.864 (95% CI, 0.798-0.930), 0.964 (95% CI, 0.903-1.000) and 0.877 (95% CI, 0.759-0.996), respectively. Conclusion: This study constructed a comprehensive nomogram consisting spectral CT quantitative parameters and clinical characteristics of GC, which exhibited a robust efficiency in predicting LVI in GC patients.

7.
Phys Chem Chem Phys ; 26(17): 13395-13404, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38647031

RESUMO

Carbonaceous materials are promising candidates as anode materials for non-lithium-ion batteries (NLIBs) due to their appealing properties such as good electrical conductivity, low cost, and high safety. However, graphene, a classic two-dimensional (2D) carbon material, is chemically inert to most metal atoms, hindering its application as an electrode material for metal-ion batteries. Inspired by the unique geometry of a four-penta unit, we explore a metallic 2D carbon allotrope C5-10-16 composed of 5-10-16 carbon rings. The C5-10-16 monolayer is free from any imaginary frequencies in the whole Brillouin zone. Due to the introduction of a non-sp2 hybridization state into C5-10-16, the extended conjugation of π-electrons is disrupted, leading to the enhanced surface activity toward metal ions. We investigate the performance of C5-10-16 as the anode for sodium/potassium-ion batteries by using first-principles calculations. The C5-10-16 sheet has high theoretical specific capacities of Na (850.84 mA h g-1) and K (743.87 mA h g-1). Besides, C5-10-16 exhibits a moderate migration barrier of 0.63 (0.32) eV for Na (K), ensuring rapid charging/discharging processes. The average open-circuit voltages of Na and K are 0.33 and 0.62 V, respectively, which are within the voltage acceptance range of anode materials. The fully sodiated (potassiated) C5-10-16 shows tiny lattice expansions of 1.4% (1.3%), suggesting the good reversibility. Moreover, bilayer C5-10-16 significantly affects both the adsorption strength and the mobility of Na or K. All these results show that C5-10-16 could be used as a promising anode material for NLIBs.

8.
Front Endocrinol (Lausanne) ; 15: 1306091, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38686208

RESUMO

Purpose: Whether the diagnosis of non-alcoholic fatty liver disease or metabolic dysfunction-associated fatty disease has a different impact on liver transplant recipients with hepatocellular carcinoma is not yet clear. Methods: Data from a two-center retrospective cohort study were collected to compare and investigate the differences between non-alcoholic fatty liver disease and metabolic dysfunction-associated fatty liver disease in clinicopathologic parameters and prognosis among liver transplant recipients with hepatocellular carcinoma. Results: A total of 268 liver transplant recipients with hepatocellular carcinoma were included. The prevalence among pre- and post-transplant metabolic dysfunction-associated fatty liver disease was 10.82% and 30.22%, while for non-alcoholic fatty liver disease, it was 7.09% and 26.87%, respectively. The clinicopathological parameters were similar between the two pre-transplant groups. In contrast, the post-transplant group with metabolic dysfunction-associated fatty liver disease exhibited a higher prevalence of diabetes mellitus and a greater body mass index. However, the other parameters were similar between the two post-transplant groups (p > 0.05). Factors such as the largest tumor size > 4 cm, microvascular invasion, lack of tumor capsule, post-transplant metabolic dysfunction-associated fatty liver disease, and decreased post-transplant lymphocyte percentage were related to an increased risk of recurrence. Conclusion: In patients undergone liver transplantation for hepatocellular carcinoma, the diagnosis of metabolic dysfunction-associated fatty disease is more strongly associated with metabolic abnormalities than the diagnosis of non-alcoholic fatty liver disease and is an independent predictor of hepatocellular carcinoma recurrence.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Hepatopatia Gordurosa não Alcoólica , Humanos , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patologia , Transplante de Fígado/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/cirurgia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Masculino , Feminino , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/diagnóstico , Pessoa de Meia-Idade , Estudos Retrospectivos , Prognóstico , Adulto , Idoso
9.
Hypertens Res ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438728

RESUMO

Hypertension and atrial fibrillation are closely related. However, hypertension is already prevalent in young adults, but atrial fibrillation usually occurs in the elderly. In the present analysis, we investigated incident atrial fibrillation in relation to new-onset hypertension in an elderly Chinese population. Our study participants were elderly (≥65 years) hypertensive residents, recruited from community health centers in the urban Shanghai (n = 4161). Previous and new-onset hypertension were defined as the use of antihypertensive medication or elevated systolic/diastolic blood pressure (≥140/90 mmHg), respectively, at entry and during follow-up on ≥ 2 consecutive clinic visits. Atrial fibrillation was detected by a 30-s single-lead electrocardiography (ECG, AliveCor® Heart Monitor) and further evaluated with a regular 12-lead ECG. During a median of 2.1 years follow-up, the incidence rate of atrial fibrillation was 7.60 per 1000 person-years in all study participants; it was significantly higher in patients with new-onset hypertension (n = 368) than those with previous hypertension (n = 3793, 15.76 vs. 6.77 per 1000 person-years, P = 0.02). After adjustment for confounding factors, the hazard ratio for the incidence of atrial fibrillation was 2.21 (95% confidence interval 1.15-4.23, P = 0.02) in patients with new-onset hypertension versus those with previous hypertension. The association was even stronger in those aged ≥ 75 years (hazard ratio 2.70, 95% confidence interval 1.11-6.56, P = 0.03). In patients with previous hypertension, curvilinear association (P for non-linear trend = 0.04) was observed between duration of hypertension and the risk of incident atrial fibrillation, with a higher risk in short- and long-term than mid-term duration of hypertension. Our study showed a significant association between new-onset hypertension and the incidence of atrial fibrillation in elderly Chinese. In an elderly Chinese population with previous and new-onset hypertension, we found that the new-onset hypertension during follow-up, compared with previous hypertension, was associated with a significantly higher risk of incident atrial fibrillation. In patients with previous hypertension, curvilinear association was observed between duration of hypertension and the risk of incident atrial fibrillation, with a higher risk in short- and long-term than mid-term duration of hypertension.

10.
Front Public Health ; 12: 1291916, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38435285

RESUMO

Purpose: In response to the growing challenges posed by an aging society, a telemedicine system was developed specifically for older adults postoperative patients, and its effectiveness was thoroughly investigated. Methods: Between May 2020 and May 2022, a total of 88 older adults postoperative patients were enrolled and randomly allocated into an experimental group and a control group. The experimental group received telemedicine services after discharge, while the control group received conventional medical services following the traditional protocol. One month after discharge, various indicators were evaluated for both groups, including number of visits, medical expenditures, postoperative recovery, anxiety, depression and satisfaction. Results: The number of visits and medical expenditures of the experimental group were less than those of the control group [1 (0, 1) vs. 1 (1, 2), Z = -3.977, p < 0.001; 25.25 (0.00, 277.40) yuan vs. 174.65 (49.63, 446.10) yuan, Z = -2.150, p = 0.032]. In both groups, there were 2 cases of incision infection, respectively. No significant difference was observed between the two groups (Fisher χ2, p = 0.259). In both groups, there was no instance of incision bleeding, incision dehiscence, readmission, or reoperation. Additionally, there was no significant difference in physical status between the two groups at discharge and after discharge (66.06 ± 8.92 vs. 65.45 ± 7.39 t = 0.287, p = 0.775; 73.33 ± 9.97 vs. 70.91 ± 7.50, t = 1.202, p = 0.235). And there was no significant difference in the change of physical status between the two groups after discharge [10.00 (0.00, 10.00) vs. 5.00 (0.00, 10.00), Z = -1.077, p = 0.281]. There was no significant difference in body weight change between the two groups after discharge [1.05 (0.38, 1.60) Kg vs. 0.80 (0.50, 1.43) Kg, Z = -0.265, p = 0.791]. There was no significant difference in the levels of anxiety and depression between the two groups at discharge (45.64 ± 8.10 vs. 44.60 ± 8.24, t = 0.520, p = 0.604, 48.33 ± 8.46 vs. 47.50 ± 6.85, t = 0.418, p = 0.677). But the levels of anxiety and depression in the experimental group were lower than those in the control group after discharge (34.92 ± 7.38 vs. 39.03 ± 8.42, t = -2.183, p = 0.032, 37.86 ± 7.29 vs. 41.93 ± 7.13, t = -2.281, p = 0.025); The change of anxiety level and depression level of the experimental group were more than those of the control group [-10.00 (-11.25, -8.75) vs. -5.00 (-7.81, -3.75), Z = -5.277, p < 0.001; -10.00 (-12.50, -7.50) vs. -5.00 (-7.75, -3.44), Z = -4.596, p < 0.001]. The level of satisfaction regarding medical services, daily care, and psychological comfort was higher in the experimental group compared to the control group [3 (3, 3.25) vs. 2 (1, 2), Z = -5.931, p < 0.001; 3 (3, 4) vs. 3 (2, 3), Z = -2.286, p = 0.022; 2 (1, 3) vs. 1 (0.75, 2), Z = -2.081, p = 0.037]. Conclusion: In the context of an aging society, telemedicine system can offer improved healthcare to older adults postoperative patients. This includes benefits such as reducing number of visits, saving medical expenditures, enhancing psychological comfort and daily care.


Assuntos
Telemedicina , Humanos , Idoso , Estudos de Viabilidade , Ansiedade , Transtornos de Ansiedade , Envelhecimento
11.
Nat Prod Res ; : 1-5, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38516729

RESUMO

Bufo gargarizans Cantor (B. gargarizans) is the most widely distributed and abundant species of toad in China. Bufadienolides and indole alkaloids have cardiotonic and anti-tumor activities and are important pharmacological components of B. bufo gargarizans. In this experiment, a novel compound (1) and two known compounds (2 and 3) were isolated and identified from the dry skin of B. bufo gargarizans, both of which are bufadienolides. Various column chromatography methods were used to separate and purify the extract from the dried skin of B. bufo gargarizans. Accurate molecular weights were measured by HR-ESI-MS, and the chemical structure of the compounds was determined by NMR spectrometers. The structures were named as (2ß,5ß,16α)-2,5,16-trihydroxide bufa-14,20,22 dienolide (1), gamabufotalin (2) and desacetylbufotalin (3). In vitro cytotoxic activity assay indicated that compound 1 showed a moderate cytotoxicity against A549 cells with IC50 value of 12.65 µM.

12.
Neurocrit Care ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480608

RESUMO

BACKGROUND: In this study, we aimed to investigate the risk factors and impact of poststroke pneumonia (PSP) on mortality and functional outcome in patients with acute ischemic stroke (AIS) after endovascular thrombectomy (EVT). METHODS: This was a post hoc analysis of a prospective randomized trial (Direct intraarterial thrombectomy in order to revascularize AIS patients with large-vessel occlusion efficiently in Chinese tertiary hospitals: a multicenter randomized clinical trial). Patients with AIS who completed EVT were evaluated for the occurrence of PSP during the hospitalization period and their modified Rankin Scale (mRS) scores at 90 days after AIS. Logistic regression analysis was conducted to investigate the independent predictors of PSP. Propensity score matching was conducted for the PSP and non-PSP groups by using the covariates resulting from the logistic regression analysis. The associations between PSP and outcomes were analyzed. The outcomes included 90-day poor functional outcome (mRS scores > 2), 90-day mortality, and early 2-week mortality. RESULTS: A total of 639 patients were enrolled, of whom 29.58% (189) developed PSP. Logistic regression analysis revealed that history of chronic heart failure (unadjusted odds ratio [OR] 2.011, 95% confidence interval [CI] 1.026-3.941; P = 0.042), prethrombectomy reperfusion on initial digital subtraction angiography (OR 0.394, 95% CI 0.161-0.964; P = 0.041), creatinine levels at admission (OR 1.008, 95% CI 1.000-1.016; P = 0.049), and National Institutes of Health Stroke Scale at 24 h (OR 1.023, 95% CI 1.007-1.039; P = 0.004) were independent risk factors for PSP. With propensity scoring matching, poor functional outcome (mRS > 2) was more common in patients with PSP than in patients without PSP (81.03% vs. 71.83%, P = 0.043) at 90 days after EVT. The early 2-week mortality of patients with PSP was lower (5.74% vs. 12.07%, P = 0.038). But there was no statistically significant difference in 90-day mortality between the PSP group and non-PSP group (22.41% vs. 14.94%, P = 0.074). The survivorship curve also shows no statistical significance (P = 0.088) between the two groups. CONCLUSIONS: Nearly one third of patients with AIS and EVT developed PSP. Heart failure, higher creatinine levels, prethrombectomy reperfusion, and National Institutes of Health Stroke Scale at 24 h were associated with PSP in these patients. PSP was associated with poor 90-day functional outcomes in patients with AIS treated with EVT.

13.
Sensors (Basel) ; 24(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38475093

RESUMO

With the advancement of engineering techniques, underground shield tunneling projects have also started incorporating emerging technologies to monitor the forces and displacements during the construction and operation phases of shield tunnels. Monitoring devices installed on the tunnel segment components generate a large amount of data. However, due to various factors, data may be missing. Hence, the completion of the incomplete data is imperative to ensure the utmost safety of the engineering project. In this research, a missing data imputation technique utilizing Random Forest (RF) is introduced. The optimal combination of the number of decision trees, maximum depth, and number of features in the RF is determined by minimizing the Mean Squared Error (MSE). Subsequently, complete soil pressure data are artificially manipulated to create incomplete datasets with missing rates of 20%, 40%, and 60%. A comparative analysis of the imputation results using three methods-median, mean, and RF-reveals that this proposed method has the smallest imputation error. As the missing rate increases, the mean squared error of the Random Forest method and the other two methods also increases, with a maximum difference of about 70%. This indicates that the random forest method is suitable for imputing monitoring data.

15.
Front Microbiol ; 15: 1328289, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38333582

RESUMO

Introduction: Citrus chlorotic dwarf-associated virus (CCDaV) is an economically important citrus virus associated with leaf curling, deformation, and chlorosis found in China. Plants have evolved RNA silencing to defend against viral infections; however, the mechanism by which CCDaV suppresses RNA silencing in citrus remains unknown. Methods: Six proteins encoded by CCDaV were ectopically expressed in Nicotiana benthamiana 16c using the pCHF3 vector to identify RNA-silencing suppression activities. Results: V2 protein encoded by CCDaV suppressed local RNA silencing and systemic RNA silencing triggered by GFP RNA, but did not impede short-distance movement of the RNA silencing signal in N. benthamiana 16c. GFP fluorescence observations showed that the ability of V2 protein to suppress RNA silencing was weaker than tomato bushy stunt virus P19. Deletion analysis showed that the putative nuclear localization signal (NLS, 25-54 aa) was involved in the RNA silencing suppression activity of V2 protein. Furthermore, V2 protein cannot block dsRNA-triggered RNA silencing. The subcellular localization assay suggested that V2 protein was localized to nucleus of N. benthamiana. Conclusion: Overall, the results of this study demonstrate that CCDaV-V2 acts as an activity of silencing suppression. This is the first reported RNA-silencing suppressor encoded by Citlodavirus and will be valuable in revealing the molecular mechanism of CCDaV infection.

16.
Sensors (Basel) ; 24(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38339583

RESUMO

The confining pressure has a great effect on the internal force of the tunnel. During construction, the confining pressure which has a crucial impact on tunnel construction changes due to the variation of groundwater level and applied load. Therefore, the safety of tunnels must have the magnitude of confining pressure accurately estimated. In this study, a complete tunnel confining pressure time axis was obtained through high-frequency field monitoring, the data are segmented into a training set and a testing set. Using GRU and RNN models, a confining pressure prediction model was established, and the prediction results were analyzed. The results indicate that the GRU model has a fast-training speed and higher accuracy. On the other hand, the training speed of the RNN model is slow, with lower accuracy. The dynamic characteristics of soil pressure during tunnel construction require accurate prediction models to maintain the safety of the tunnel. The comparison between GRU and RNN models not only highlights the advantages of the GRU model but also emphasizes the necessity of balancing speed accuracy in tunnel construction confining pressure prediction modeling. This study is helpful in improving the understanding of soil pressure dynamics and developing effective prediction tools to promote safer and more reliable tunnel construction practices.

17.
Sheng Wu Gong Cheng Xue Bao ; 40(2): 517-528, 2024 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-38369838

RESUMO

The α-1 antitrypsin Z-mutant protein (ATZ) is the primary cause of α-1 antitrypsin deficiency (AATD). Studying the ubiquitination modification and degradation of ATZ protein is importance for developing treatments for AATD. STUB1 is an important E3 ubiquitin ligase that regulates ubiquitination modification of various proteins. However, whether STUB1 in involved in the ubiquitination modification of ATZ has not been fully elucidated. In this study, the ATZ and STUB1 coding genes were first cloned into the pET28a plasmid, constructing 2 protein expression plasmids. The recombinant plasmids were then transferred into the Escherichia coli for expression. With the optimization of induction temperature and IPTG dosage, the recombinant proteins were successfully expressed. The target proteins were then efficiently purified from cell lysates using metal-chelating affinity chromatography, and the accuracy of the amino acid sequence was verified through protein mass spectrometry analysis. Using the purified ATZ and STUB1, we established an in vitro ubiquitination reaction system. Experimental results showed that, in the presence of ATP, E1 ubiquitin-activating enzyme, and E2 ubiquitin-conjugating enzyme, STUB1 catalyzed the ubiquitination modification of ATZ. This study provides a method for obtaining the ATZ protein in vitro, elucidates the mechanism of STUB1 mediating ATZ ubiquitination, thereby advancing our understanding of the intracellular degradation mechanism of the α-1 antitrypsin Z-mutant.


Assuntos
Ubiquitina-Proteína Ligases , Ubiquitinação , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
18.
Sensors (Basel) ; 24(4)2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38400469

RESUMO

The construction of large-diameter shield tunnels underwater involves complex variations in water and earth load outside the tunnel segment, as well as intricate mechanical responses. This study analyzes the variation laws of external loads, axial forces, and bending moments acting on the segment ring during the shield assembly and removal from the shield tail. It accomplishes this through the establishment of an on-site monitoring system based on the Internet of Things (IoT) and proposes a Bayesian-genetic algorithm model to estimate the water and earth pressure. The fluctuation section exhibits a peak load twice as high as that in the stable section. These variations are influenced by Jack thrust, shield shell force, and grouting pressure. The peak load observed in the fluctuation section is twice as high as the load observed in the stable section. During the shield tail removal process, the internal forces undergo significant fluctuations due to changes in both load and boundary conditions, and the peak value of the axial force during the fluctuation section is eight times higher than that during the stable section, while the peak value of the bending moment during the fluctuation section is five times higher than that during the stable section. The earth and water pressure calculated using the inversion analysis method, which relies on the measured internal forces, closely matches the actual measured values. The results demonstrate that the accuracy of the water and earth pressure obtained through inversion analysis is twice as high as that obtained using the full coverage pressure method. These results can serve as a valuable reference for similar projects.

19.
J Phys Chem Lett ; 15(9): 2485-2492, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38408427

RESUMO

We propose a two-dimensional carbon allotrope (named KT-graphene) by incorporating kagome and tetragonal lattices consisting of trigonal, quadrilateral, octagonal, and dodecagonal rings. The introduction of non-hexagonal rings can give rise to the localized electronic states that improve the chemical reactivity toward potassium, making KT-graphene a high-performance anode material for potassium-ion batteries. It shows a high theoretical capacity (892 mAh g-1), a low diffusion barrier (0.33 eV), and a low average open-circuit voltage (0.51 V). The presence of electrolyte solvents is propitious to boost the K-ion adsorption and diffusion capabilities. Moreover, one-dimensional nanotubes (KT-CNTs), rolled up by the KT-graphene sheet, are metallic regardless of the tube diameter. As the curvature increases, KT-CNTs exhibit significantly increased surface activity, which can promote the electron-donating ability of K. Furthermore, the curvature effect greatly enhances the efficiency of K diffusion on the inner surface compared to that on the outer surface.

20.
Phytochem Anal ; 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191170

RESUMO

INTRODUCTION: Steroidal saponins characterised by intricate chemical structures are the main active components of a well-known traditional Chinese medicine (TCM) Rhizoma Paridis. The metabolic profiles of steroidal saponins in vivo remain largely unexplored, despite their renowned antitumor, immunostimulating, and haemostatic activity. OBJECTIVE: To perform a comprehensive analysis of the chemical constituents of Rhizoma Paridis total saponins (RPTS) and their metabolites in rats after oral administration. METHOD: The chemical constituents of RPTS and their metabolites were analysed using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS). RESULTS: A reliable UPLC-Q-TOF-MS/MS method was established, and a total of 142 compounds were identified in RPTS. Specifically, diosgenin-type saponins showed the diagnostic ions at m/z 415.32, 397.31, 283.25, 271.21, and 253.20, whereas pennogenin-type saponins exhibited the diagnostic ions at m/z 413.31, 395.30, and 251.20. Based on the characteristic fragments and standard substances, 15 specific metabolites were further identified in the faeces, urine, plasma, and bile of rats. The metabolic pathways of RPTS, including phase I reactions (de-glycosylation and oxidation) and phase II reactions (glucuronidation), were explored and summarised, and the enrichment of metabolites was characterised by multivariate statistical analysis. CONCLUSION: The intricate RPTS could be transformed into relatively simple metabolites in rats through de-glycosylation, which provides a reference for further metabolic studies and screening of active ingredients for TCM.

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