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1.
J Biol Chem ; 300(7): 107425, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38823639

RESUMEN

Adenosine deaminase (ADA) catalyzes the irreversible deamination of adenosine (ADO) to inosine and regulates ADO concentration. ADA ubiquitously expresses in various tissues to mediate ADO-receptor signaling. A significant increase in plasma ADA activity has been shown to be associated with the pathogenesis of type 2 diabetes mellitus. Here, we show that elevated plasma ADA activity is a compensated response to high level of ADO in type 2 diabetes mellitus and plays an essential role in the regulation of glucose homeostasis. Supplementing with more ADA, instead of inhibiting ADA, can reduce ADO levels and decrease hepatic gluconeogenesis. ADA restores a euglycemic state and recovers functional islets in db/db and high-fat streptozotocin diabetic mice. Mechanistically, ADA catabolizes ADO and increases Akt and FoxO1 phosphorylation independent of insulin action. ADA lowers blood glucose at a slower rate and longer duration compared to insulin, delaying or blocking the incidence of insulinogenic hypoglycemia shock. Finally, ADA suppresses gluconeogenesis in fasted mice and insulin-deficient diabetic mice, indicating the ADA regulating gluconeogenesis is a universal biological mechanism. Overall, these results suggest that ADA is expected to be a new therapeutic target for diabetes.

2.
J Biol Chem ; 299(10): 105219, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37660913

RESUMEN

Rectal prolapse in serious inflammatory bowel disease is caused by abnormal reactions of the intestinal mucosal immune system. The circadian clock has been implicated in immune defense and inflammatory responses, but the mechanisms by which it regulates gut inflammation remain unclear. In this study, we investigate the role of the rhythmic gene Period2 (Per2) in triggering inflammation in the rectum and its contribution to the pathogenesis of rectal prolapse. We report that Per2 deficiency in mice increased susceptibility to intestinal inflammation and resulted in spontaneous rectal prolapse. We further demonstrated that PER2 was essential for the transcription of glycogen synthase 1 by interacting with the NF-κB p65. We show that the inhibition of Per2 reduced the levels of glycogen synthase 1 and glycogen synthesis in macrophages, impairing the capacity of pathogen clearance and disrupting the composition of gut microbes. Taken together, our findings identify a novel role for Per2 in regulating the capacity of pathogen clearance in macrophages and gut inflammation and suggest a potential animal model that more closely resembles human rectal prolapse.

3.
BMC Plant Biol ; 24(1): 516, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38851686

RESUMEN

BACKGROUND: The influence of native secondary succession associated with anthropogenic disturbance on the biodiversity of the forests in subtropical China remains uncertain. In particular, the evolutionary response of small understory shrubs, particularly pioneer species inhabiting continuously disturbed habitats, to topographic heterogeneity and climate change is poorly understood. This study aimed to address this knowledge gap by focusing on the Gaultheria crenulata group, a clade of small pioneer shrubs in subtropical China. RESULTS: We examined the genetic structure and demographic history of all five species of the G. crenulata group with two maternally inherited chloroplast DNA (cpDNA) fragments and two biparentally inherited low-copy nuclear genes (LCG) over 89 natural populations. We found that the genetic differentiation of this group was influenced by the geomorphological boundary between different regions of China in association with Quaternary climatic events. Despite low overall genetic diversity, we observed an isolation-by-distance (IBD) pattern at a regional scale, rather than isolation-by-environment (IBE), which was attributed to ongoing human disturbance in the region. CONCLUSION: Our findings suggest that the genetic structure of the G. crenulata group reflects the interplay of geological topography, historical climates, and anthropogenic disturbance during the Pliocene-Pleistocene-Holocene periods in subtropical China. The observed IBD pattern, particularly prominent in western China, highlights the role of limited dispersal and gene flow, possibly influenced by physical barriers or decreased connectivity over geographic distance. Furthermore, the east-to-west trend of gene flow, potentially facilitated by the East Asian monsoon system, underscores the complex interplay of biotic and abiotic factors shaping the genetic dynamics of pioneer species in subtropical China's secondary forests. These findings can be used to assess the impact of environmental changes on the adaptation and persistence of biodiversity in subtropical forest ecosystems.


Asunto(s)
Bosques , Variación Genética , China , ADN de Cloroplastos/genética , Dinámica Poblacional , Biodiversidad , Flujo Génico
4.
Analyst ; 149(11): 3195-3203, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38651605

RESUMEN

Extracellular vesicles (EVs) originating from cancer cells incorporate various critical biomolecules that can aid in early cancer diagnosis. However, the rapid analysis of these micro vesicles remains challenging due to their nano-scale size and overlapping dimensions, hindering sufficient capture in terms of quantity and purity. In this study, an acoustofluidic device was developed to enhance the yield of immune-captured EVs. The channel of the device was modified with degradable gelatin nanoparticles (∼220 nm) to increase the surface roughness, and subsequently treated with CD63 antibodies. The acoustic-induced streaming would prolong the rotation time of the EVs in the targeted continuous flow area, improving their aggregation towards the surrounding pillars and subsequent capture by the specific CD63 antibodies. Consequently, the capture efficiency of the device was improved when the signal was on, as evidenced by enhanced fluorescence intensity in the main channel. It is demonstrated that the acoustofluidic device could enhance the immune capture of EVs through acoustic mixing, showcasing great potential in the rapid and fast detection of EVs in liquid biopsy applications.


Asunto(s)
Vesículas Extracelulares , Gelatina , Nanopartículas , Tetraspanina 30 , Gelatina/química , Vesículas Extracelulares/química , Vesículas Extracelulares/inmunología , Nanopartículas/química , Humanos , Tetraspanina 30/metabolismo , Acústica , Dispositivos Laboratorio en un Chip
5.
Molecules ; 29(8)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38675587

RESUMEN

Solid-state hydrogen storage technology has emerged as a disruptive solution to the "last mile" challenge in large-scale hydrogen energy applications, garnering significant global research attention. This paper systematically reviews the Chinese research progress in solid-state hydrogen storage material systems, thermodynamic mechanisms, and system integration. It also quantitatively assesses the market potential of solid-state hydrogen storage across four major application scenarios: on-board hydrogen storage, hydrogen refueling stations, backup power supplies, and power grid peak shaving. Furthermore, it analyzes the bottlenecks and challenges in industrialization related to key materials, testing standards, and innovation platforms. While acknowledging that the cost and performance of solid-state hydrogen storage are not yet fully competitive, the paper highlights its unique advantages of high safety, energy density, and potentially lower costs, showing promise in new energy vehicles and distributed energy fields. Breakthroughs in new hydrogen storage materials like magnesium-based and vanadium-based materials, coupled with improved standards, specifications, and innovation mechanisms, are expected to propel solid-state hydrogen storage into a mainstream technology within 10-15 years, with a market scale exceeding USD 14.3 billion. To accelerate the leapfrog development of China's solid-state hydrogen storage industry, increased investment in basic research, focused efforts on key core technologies, and streamlining the industry chain from materials to systems are recommended. This includes addressing challenges in passenger vehicles, commercial vehicles, and hydrogen refueling stations, and building a collaborative innovation ecosystem involving government, industry, academia, research, finance, and intermediary entities to support the achievement of carbon peak and neutrality goals and foster a clean, low-carbon, safe, and efficient modern energy system.

6.
Molecules ; 29(11)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38893327

RESUMEN

Magnesium-based hydrogen storage materials have garnered significant attention due to their high hydrogen storage capacity, abundance, and low cost. However, the slow kinetics and high desorption temperature of magnesium hydride hinder its practical application. Various preparation methods have been developed to improve the hydrogen storage properties of magnesium-based materials. This review comprehensively summarizes the recent advances in the preparation methods of magnesium-based hydrogen storage materials, including mechanical ball milling, methanol-wrapped chemical vapor deposition, plasma-assisted ball milling, organic ligand-assisted synthesis, and other emerging methods. The principles, processes, key parameters, and modification strategies of each method are discussed in detail, along with representative research cases. Furthermore, the advantages and disadvantages of different preparation methods are compared and evaluated, and their influence on hydrogen storage properties is analyzed. The practical application potential of these methods is also assessed, considering factors such as hydrogen storage performance, scalability, and cost-effectiveness. Finally, the existing challenges and future research directions in this field are outlined, emphasizing the need for further development of high-performance and cost-effective magnesium-based hydrogen storage materials for clean energy applications. This review provides valuable insights and references for researchers working on the development of advanced magnesium-based hydrogen storage technologies.

7.
Molecules ; 29(11)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38893401

RESUMEN

Magnesium-based hydrogen storage alloys have attracted significant attention as promising materials for solid-state hydrogen storage due to their high hydrogen storage capacity, abundant reserves, low cost, and reversibility. However, the widespread application of these alloys is hindered by several challenges, including slow hydrogen absorption/desorption kinetics, high thermodynamic stability of magnesium hydride, and limited cycle life. This comprehensive review provides an in-depth overview of the recent advances in magnesium-based hydrogen storage alloys, covering their fundamental properties, synthesis methods, modification strategies, hydrogen storage performance, and potential applications. The review discusses the thermodynamic and kinetic properties of magnesium-based alloys, as well as the effects of alloying, nanostructuring, and surface modification on their hydrogen storage performance. The hydrogen absorption/desorption properties of different magnesium-based alloy systems are compared, and the influence of various modification strategies on these properties is examined. The review also explores the potential applications of magnesium-based hydrogen storage alloys, including mobile and stationary hydrogen storage, rechargeable batteries, and thermal energy storage. Finally, the current challenges and future research directions in this field are discussed, highlighting the need for fundamental understanding of hydrogen storage mechanisms, development of novel alloy compositions, optimization of modification strategies, integration of magnesium-based alloys into hydrogen storage systems, and collaboration between academia and industry.

8.
J Lipid Res ; 64(6): 100390, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37209828

RESUMEN

Several epidemiological studies suggest a correlation between eating time and obesity. Night eating syndrome characterized by a time-delayed eating pattern is positively associated with obesity in humans as well as in experimental animals. Here, we show that oil intake at night significantly makes more fat than that at day in wild-type mice, and circadian Period 1 (Per1) contributes to this day-night difference. Per1-knockout mice are protected from high-fat diet-induced obesity, which is accompanied by a reduction in the size of the bile acid pool, and the oral administration of bile acids restores fat absorption and accumulation. We identify that PER1 directly binds to the major hepatic enzymes involved in bile acid synthesis such as cholesterol 7alpha-hydroxylase and sterol 12alpha-hydroxylase. A biosynthesis rhythm of bile acids is accompanied by the activity and instability of bile acid synthases with PER1/PKA-mediated phosphorylation pathways. Both fasting and high fat stress enhance Per1 expression, increasing the fat absorption and accumulation. Our findings reveal that Per1 is an energy regulator and controls daily fat absorption and accumulation. Circadian Per1 controls daily fat absorption and accumulation, suggesting Per1 is a potential candidate of a key regulator in stress response and the relevant obesity risk.


Asunto(s)
Ácidos y Sales Biliares , Ligasas , Animales , Ratones , Ácidos y Sales Biliares/metabolismo , Colesterol 7-alfa-Hidroxilasa/metabolismo , Ligasas/metabolismo , Hígado/metabolismo , Obesidad/metabolismo , Proteínas Circadianas Period/metabolismo , Fosforilación , Factores de Transcripción/metabolismo
9.
J Biol Chem ; 298(6): 101968, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35460695

RESUMEN

Iron accumulates with age in mammals, and its possible implications in altering metabolic responses are not fully understood. Here, we report that both high-iron diet and advanced age in mice consistently altered gene expression of many pathways, including those governing the oxidative stress response and the circadian clock. We used a metabolomic approach to reveal similarities between metabolic profiles and the daily oscillation of clock genes in old and iron-overloaded mouse livers. In addition, we show that phlebotomy decreased iron accumulation in old mice, partially restoring the metabolic patterns and amplitudes of the oscillatory expression of clock genes Per1 and Per2. We further identified that the transcriptional regulation of iron occurred through a reduction in AMP-modulated methylation of histone H3K9 in the Per1 and H3K4 in the Per2 promoters, respectively. Taken together, our results indicate that iron accumulation with age can affect metabolic patterns and the circadian clock.


Asunto(s)
Envejecimiento/patología , Código de Histonas , Proteínas Circadianas Period/genética , Adenosina Monofosfato , Envejecimiento/metabolismo , Animales , Relojes Circadianos , Ritmo Circadiano , Expresión Génica , Histonas/metabolismo , Hierro , Mamíferos , Metilación , Ratones , Factores de Transcripción/genética
10.
J Antimicrob Chemother ; 78(3): 828-831, 2023 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-36719104

RESUMEN

BACKGROUND AND OBJECTIVES: High-dose dual therapy [proton pump inhibitor (PPI) + amoxicillin] is recommended as a Helicobacter pylori rescue treatment. However, its efficacy is still controversial. The aim of this study was to evaluate the efficacy and safety of triple therapy containing high dose of PPI and amoxicillin plus metronidazole compared with dual therapy in rescue treatment. METHODS: Two hundred and sixty-eight patients who failed at least two courses of H. pylori treatment were recruited and randomly allocated into two 14-day groups: esomeprazole 40 mg twice daily and amoxicillin 1000 mg three times daily plus metronidazole 400 mg three times daily (EAM group); or esomeprazole 40 mg twice daily and amoxicillin 1000 mg three times daily (EA group). The agar-dilution method was performed as an antibiotic susceptibility test. The 13C urea breath test was used to assess H. pylori eradication at 6 weeks after the treatment. The study was registered at clinicaltrials.gov (NCT04024527). RESULTS: H. pylori eradication rates in the EAM group were 85.8% (115/134, 95% CI 79.9%-91.7%) in ITT analysis and 92.6% (113/122, 95% CI 87.9%-97.3%) in PP analysis, significantly higher than those of the EA group, which were 73.1% (98/134, 95% CI 65.6%-80.6%) and 83.1% (98/118, 95% CI 76.8%-89.8%) (P = 0.005, 0.011). Resistance rates of amoxicillin and metronidazole were 6.6% (13/196) and 89.8% (176/196). Metronidazole resistance did not affect the eradication rates in the EAM group. Both groups had similar moderate and severe adverse events and similar compliance. CONCLUSIONS: A triple therapy containing high dose of PPI and amoxicillin plus metronidazole could be a potential rescue therapy worldwide even in a high metronidazole-resistance region.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Humanos , Metronidazol/uso terapéutico , Antibacterianos/farmacología , Esomeprazol , Infecciones por Helicobacter/tratamiento farmacológico , Quimioterapia Combinada , Amoxicilina , Inhibidores de la Bomba de Protones , Resultado del Tratamiento , Claritromicina/uso terapéutico
11.
Nanotechnology ; 34(24)2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36917847

RESUMEN

Two-dimensional (2D) MoSi2N4is a newly created material that has superstability and ultrahigh carrier mobility. Besides, the hydrogen evolution reaction activity was proved excellent by doping transition metal (TM) atoms and introducing N vacancies. But, the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) of 2D MoSi2N4is unclear even. We have explored the electrocatalytic properties (OER/ORR) of MoSi2N4by introducing Si vacancies and attaching various TM atoms. The structure and optoelectronic characteristics of MoSi2N4have been researched in detail using density functional theory calculations. By analyzing the density of states, the free energy change diagram and contour maps of TM@VSi-MoSiN, the results show that Co@VSi-MoSiN has the lowest OER overpotential (0.53 V) among all samples. Additionally, the d-band center is used to explain the electrocatalytic origin of the OER and ORR of TM@VSi-MoSiN. Our discoveries expand the 2D TM@VSi-MoSiN applicability in the realm of catalysis.

12.
Int J Colorectal Dis ; 38(1): 53, 2023 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-36840832

RESUMEN

BACKGROUND: Total proctocolectomy (TPC) with ileal pouch-anal anastomosis (IPAA) has been accepted as a radical surgery for refractory ulcerative colitis (UC). We aimed to assess the predictive value of several novel and widely used endoscopic core systems, The Toronto IBD Global Endoscopic Reporting (TIGER) score, Mayo endoscopic score (MES), and ulcerative colitis endoscopic index of severity (UCEIS) in guiding the need for IPAA. METHODS: Data on patients with UC from June 1986 and June 2022 at our institute were collected. The endoscopic evaluation was recorded according to the first colonoscopy after hospitalization. Primary outcome was the need for IPAA during admission and follow-up. RESULTS: A total of 313 patients with a median follow-up time and a median TIGER score of 12.0 years (interquartile range (IQR): 6.0-17.0) and 212.0 (IQR: 7.0-327.0) were enrolled. IPAA was conducted in 110 (35.1%) patients, which significantly improved the long-term quality of life. TIGER score had the biggest area under the receiver-operating characteristic curve of 0.810 with a sensitivity of 75.0% and specificity of 87.1% at the cut-off value of 315 (p < 0.001). TIGER score ≥ 315 was an independent risk factor with the highest odds ratio for the need for IPAA and associated with the shortest IPAA-free survival time compared with UCEIS and MES. CONCLUSION: TIGER score was superior to UCEIS and MES in predicting the need for IPAA. For colorectal surgeons, three or more segments with moderate-to-severe endoscopic activity should be considered as a threshold value for decision-making for IPAA.


Asunto(s)
Colitis Ulcerosa , Reservorios Cólicos , Proctocolectomía Restauradora , Humanos , Colitis Ulcerosa/cirugía , Calidad de Vida , Colonoscopía , Anastomosis Quirúrgica , Estudios Retrospectivos
13.
Int J Colorectal Dis ; 38(1): 15, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36648457

RESUMEN

BACKGROUND: Intraoperative intravenous fluid administration proves to be associated with surgical patients' postoperative outcomes. Few studies reported the relationship between intraoperative crystalloid-colloid infusion ratio and early surgical complications after ileal pouch-anal anastomosis (IPAA) in ulcerative colitis (UC). METHODS: Data on patients with underwent IPAA from January 2008 to March 2022 at our three inflammatory bowel disease (IBD) surgery centers were retrospectively collected. Intraoperative anesthetic data were recorded and later evaluated by our team anesthesiologist. RESULTS: A total of 140 eligible patients with a median follow-up time of 6.0 years [interquartile range (IQR): 2.0-8.0] were enrolled. Among all enrolled patients, 34 (24.3%) developed early surgical complications after IPAA. Greater blood loss and lower crystalloid-colloid infusion ratio were observed in patients with early surgical complications. Crystalloid-colloid infusion ratio < 2 and blood loss ≥ 200 ml had the most significant area under the receiver-operating characteristic curve (AUC) of 0.664 and 0.674 in predicting early surgical complications. Crystalloid-colloid infusion ratio < 2 [odds ratio (OR), 2.571; 95% confidence intervals (CI), 1.067-6.195, p = 0.035] and blood loss ≥ 200 ml (OR, 3.165; 95% CI, 1.288-7.777, p = 0.012) were independent risk factors for the development of early post-IPAA complications. CONCLUSION: Intraoperative crystalloid-colloid infusion ratio < 2 and blood loss volume over 200 ml during IPAA contribute to the occurrence of early surgical complications. Early attentions and necessary interventions are warranted to avoid these risk factors during the IPAA surgery in order to prevent the development of early surgical complications.


Asunto(s)
Colitis Ulcerosa , Reservorios Cólicos , Proctocolectomía Restauradora , Humanos , Colitis Ulcerosa/cirugía , Colitis Ulcerosa/complicaciones , Estudios de Seguimiento , Estudios Retrospectivos , Soluciones Cristaloides , Proctocolectomía Restauradora/efectos adversos , Anastomosis Quirúrgica/efectos adversos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Reservorios Cólicos/efectos adversos , Resultado del Tratamiento
14.
J Therm Biol ; 114: 103563, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37344025

RESUMEN

Thermal burn injury is a severe and life-threatening form of trauma that presents a significant challenge to clinical therapy. Therapeutic hypothermia has been shown to be beneficial in various human pathologies. Adenosine triphosphate (ATP) induces a hypothermic state that resembles hibernation-like suspended animation in mammals. This study investigates the potential protective role of ATP-induced hypothermia in thermal burn injury. Male C57BL/6 mice underwent a sham procedure or third-degree burn, and ATP-induced hypothermia was applied immediately or 1 h after burn injury. Our results show that ATP-induced hypothermia significantly improved burn depth progression and reduced collagen degradation. Moreover, hypothermia induced by ATP alleviated burn-induced hyperinflammatory responses and oxidative stress. Metabolomic profiling revealed that ATP-induced hypothermia reversed the shifts of metabolic profiles of the skin in burn mice. In addition, ATP-induced hypothermia relieved nociceptive and inflammatory pain, as observed in the antinociceptive test. Our findings suggest that ATP-induced hypothermia attenuates burn injury and provides new insights into first-aid therapy after thermal burn injury.


Asunto(s)
Quemaduras , Hipotermia Inducida , Hipotermia , Animales , Masculino , Ratones , Adenosina Trifosfato , Quemaduras/complicaciones , Quemaduras/terapia , Hipotermia/terapia , Hipotermia Inducida/métodos , Mamíferos , Ratones Endogámicos C57BL , Dolor
15.
Molecules ; 28(21)2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37959804

RESUMEN

Superparamagnetic magnetic nanoparticles (MNPs, Fe3O4) were first synthesized based on a chemical co-precipitation method, and the core-shell magnetic silica nanoparticles (MSNPs, Fe3O4@SiO2) were obtained via hydrolysis and the condensation of tetraethyl orthosilicate onto Fe3O4 seed using a sol-gel process. Following that, MSNPs were immobilized using a three-step grafting strategy, where 8-hloroacetyl-aminoquinoline (CAAQ) was employed as a metal ion affinity ligand for trapping specific heavy metal ions, and a macromolecular polymer (polyethylenimine (PEI)) was selected as a bridge between the surface hydroxyl group and CAAQ to fabricate a network of organic networks onto the MSNPs' surface. The as-synthesized MSNPs-CAAQ nanocomposites possessed abundant active functional groups and thus contained excellent removal features for heavy metal ions. Specifically, the maximum adsorption capacities at room temperature and without adjusting pH were 324.7, 306.8, and 293.3 mg/g for Fe3+, Cu2+, and Cr3+ ions, respectively, according to Langmuir linear fitting. The adsorption-desorption experiment results indicated that Na2EDTA proved to be more suitable as a desorbing agent for Cr3+ desorption on the MSNPs-CAAQ surface than HCl and HNO3. MSNPs-CAAQ exhibited a satisfactory adsorption capacity toward Cr3+ ions even after six consecutive adsorption-desorption cycles; the adsorption efficiency for Cr3+ ions was still 88.8% with 0.1 mol/L Na2EDTA as the desorbing agent. Furthermore, the MSNPs-CAAQ nanosorbent displayed a strong magnetic response with a saturated magnetization of 24.0 emu/g, and they could be easily separated from the aqueous medium under the attraction of a magnet, which could facilitate the sustainable removal of Cr3+ ions in practical applications.

16.
Molecules ; 28(16)2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37630256

RESUMEN

CeO2 is an important rare earth (RE) oxide and has served as a typical oxygen storage material in practical applications. In the present study, the oxygen storage capacity (OSC) of CeO2 was enhanced by doping with other rare earth ions (RE, RE = Yb, Y, Sm and La). A series of Undoped and RE-doped CeO2 with different doping levels were synthesized using a solvothermal method following a subsequent calcination process, in which just Ce(NO3)3∙6H2O, RE(NO3)3∙nH2O, ethylene glycol and water were used as raw materials. Surprisingly, the Undoped CeO2 was proved to be a porous material with a multilayered special morphology without any additional templates in this work. The lattice parameters of CeO2 were refined by the least-squares method with highly pure NaCl as the internal standard for peak position calibrations, and the solubility limits of RE ions into CeO2 were determined; the amounts of reducible-reoxidizable Cen+ ions were estimated by fitting the Ce 3d core-levels XPS spectra; the non-stoichiometric oxygen vacancy (VO) defects of CeO2 were analyzed qualitatively and quantitatively by O 1s XPS fitting and Raman scattering; and the OSC was quantified by the amount of H2 consumption per gram of CeO2 based on hydrogen temperature programmed reduction (H2-TPR) measurements. The maximum [OSC] of CeO2 appeared at 5 mol.% Yb-, 4 mol.% Y-, 4 mol.% Sm- and 7 mol.% La-doping with the values of 0.444, 0.387, 0.352 and 0.380 mmol H2/g by an increase of 93.04, 68.26, 53.04 and 65.22%. Moreover, the dominant factor for promoting the OSC of RE-doped CeO2 was analyzed.

17.
Zhongguo Zhong Yao Za Zhi ; 48(21): 5863-5870, 2023 Nov.
Artículo en Zh | MEDLINE | ID: mdl-38114182

RESUMEN

This study aims to investigate the effects of baicalein(BAI) on lipopolysaccharide(LPS)-induced human microglial clone 3(HMC3) cells, with a focus on suppressing inflammatory responses and elucidating the potential mechanism underlying the therapeutic effects of BAI on ischemic stroke via modulating the cAMP-PKA-NF-κB/CREB pathway. The findings have significant implications for the application of traditional Chinese medicine in treating cerebral ischemic diseases. First, the safe dosage of BAI was screened, and then an inflammation model was established with HMC3 cells by induction with LPS for 24 h. The cells were assigned into a control group, a model group, and high-, medium-, and low-dose(5, 2.5, and 1.25 µmol·L~(-1), respectively) BAI groups. The levels of superoxide dismutase(SOD) and malondialdehyde(MDA) in cell extracts, as well as the levels of interleukin-1ß(IL-1ß), IL-6, tumor necrosis factor-α(TNF-α), and cyclic adenosine monophosphate(cAMP) in the cell supernatant, were measured. Western blot was performed to determine the expression of protein kinase A(PKA), phosphorylated cAMP-response element binding protein(p-CREB), and nuclear factor-kappa B p65(NF-κB p65). Hoechst 33342/PI staining was employed to assess cell apoptosis. High and low doses of BAI were used for treatment in the research on the mechanism. The results revealed that BAI at the concentrations of 10 µmol·L~(-1) and below had no impact on normally cultured HMC3 cells. LPS induction at 200 ng·mL~(-1) for 24 h reduced the SOD activity and increased the MDA content in HMC3 cells. However, 5, 2.5, and 1.25 µmol·L~(-1) BAI significantly increased the SOD activity and 5 µmol·L~(-1) BAI significantly decreased the MDA content. In addition, BAI ameliorated the M1 polarization of HMC3 cells induced by LPS, as indicated by cellular morphology. The results of ELISA demonstrated that BAI significantly lowered the levels of TNF-α, IL-1ß, IL-6, and cAMP in the cell supernatant. Western blot revealed that BAI up-regulated the protein levels of PKA and p-CREB while down-regulating the expression of NF-κB p65. Hoechst 33342/PI staining results indicated that BAI mitigated the apoptosis of HMC3 cells. Overall, the results indicated that BAI had protective effects on the HMC3 cells induced by LPS, and could inhi-bit inflammatory response and improve cell apoptosis, which might be related to the regulation of the cAMP-PKA-NF-κB/CREB pathway.


Asunto(s)
Microglía , FN-kappa B , Humanos , FN-kappa B/genética , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Superóxido Dismutasa/metabolismo
18.
J Biol Chem ; 297(1): 100846, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34058194

RESUMEN

Hepatic gluconeogenesis is the major contributor to the hyperglycemia observed in both patients and animals with type 2 diabetes. The transcription factor FOXO1 plays a dominant role in stimulating hepatic gluconeogenesis. FOXO1 is mainly regulated by insulin under physiological conditions, but liver-specific disruption of Foxo1 transcription restores normal gluconeogenesis in mice in which insulin signaling has been blocked, suggesting that additional regulatory mechanisms exist. Understanding the transcriptional regulation of Foxo1 may be conducive to the development of insulin-independent strategies for the control of hepatic gluconeogenesis. Here, we found that elevated plasma levels of adenine nucleotide in type 2 diabetes are the major regulators of Foxo1 transcription. We treated lean mice with 5'-AMP and examined their transcriptional profiles using RNA-seq. KEGG analysis revealed that the 5'-AMP treatment led to shifted profiles that were similar to db/db mice. Many of the upregulated genes were in pathways associated with the pathology of type 2 diabetes including Foxo1 signaling. As observed in diabetic db/db mice, lean mice treated with 5'-AMP displayed enhanced Foxo1 transcription, involving an increase in cellular adenosine levels and a decrease in the S-adenosylmethionine to S-adenosylhomocysteine ratio. This reduced methylation potential resulted in declining histone H3K9 methylation in the promoters of Foxo1, G6Pc, and Pepck. In mouse livers and cultured cells, 5'-AMP induced expression of more FOXO1 protein, which was found to be localized in the nucleus, where it could promote gluconeogenesis. Our results revealed that adenine nucleotide-driven Foxo1 transcription is crucial for excessive glucose production in type 2 diabetic mice.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Proteína Forkhead Box O1/genética , Hiperglucemia/genética , Transcripción Genética/genética , Nucleótidos de Adenina/sangre , Animales , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/patología , Regulación de la Expresión Génica/genética , Gluconeogénesis/genética , Glucosa/metabolismo , Humanos , Hiperglucemia/sangre , Hiperglucemia/patología , Insulina/genética , Hígado/metabolismo , Hígado/patología , Ratones , Ratones Endogámicos NOD
19.
J Biol Chem ; 297(4): 101166, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34487763

RESUMEN

Hibernation is an example of extreme hypometabolic behavior. How mammals achieve such a state of suspended animation remains unclear. Here we show that several strains of type 2 diabetic mice spontaneously enter into hibernation-like suspended animation (HLSA) in cold temperatures. Nondiabetic mice injected with ATP mimic the severe hypothermia analogous to that observed in diabetic mice. We identified that uric acid, an ATP metabolite, is a key molecular in the entry of HLSA. Uric acid binds to the Na+ binding pocket of the Na+/H+ exchanger protein and inhibits its activity, acidifying the cytoplasm and triggering a drop in metabolic rate. The suppression of uric acid biosynthesis blocks the occurrence of HLSA, and hyperuricemic mice induced by treatment with an uricase inhibitor can spontaneously enter into HLSA similar to that observed in type 2 diabetic mice. In rats and dogs, injection of ATP induces a reversible state of HLSA similar to that seen in mice. However, ATP injection fails to induce HLSA in pigs due to the lack of their ability to accumulate uric acid. Our results raise the possibility that nonhibernating mammals could spontaneously undergo HLSA upon accumulation of ATP metabolite, uric acid.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Hibernación , Ácido Úrico/metabolismo , Adenosina Trifosfato/genética , Adenosina Trifosfato/metabolismo , Adenosina Trifosfato/farmacología , Animales , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patología , Perros , Hiperuricemia/genética , Hiperuricemia/metabolismo , Hiperuricemia/patología , Masculino , Ratones , Ratones Noqueados , Ratas , Intercambiadores de Sodio-Hidrógeno/genética , Intercambiadores de Sodio-Hidrógeno/metabolismo
20.
Langenbecks Arch Surg ; 407(1): 267-275, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34549336

RESUMEN

BACKGROUND: Anastomotic leakages (ALs) are one of the most serious complications following gastrointestinal anastomosis. Currently, very few operative measures are available for the prevention of ALs. This pilot study aimed to evaluate the safety and efficacy of tube enterostomy (T-E) for the prevention of ALs in patients with high-risk intestinal anastomosis. METHODS: In this retrospective study, demographic data and postoperative outcomes were compared among patients who received T-E and two historical cohorts: one group that underwent primary anastomosis without T-E (non-T-E group) and another that underwent conventional stoma construction without anastomosis (stoma group). The operative procedures were selected according to a scoring system that quantitatively evaluated risk of Als (Zhongnan score). RESULTS: From March 2017 to March 2020, a total of 45 consecutive patients were enrolled in the T-E group. Among these patients, 53.3% (24/45) were diagnosed with Crohn's disease (CD), and 66.7% (30/45) of them underwent emergency surgery. After propensity score matching, the demographic data were comparable among the three groups. One case of AL (2.2%) occurred in the T-E group, while four cases of ALs (8.9%, 4/45) were found in the non-T-E group (p = 0.13). Tube feeding was provided to 33.3% (15/45) of the T-E patients. Major tube-related complications included one tube dislocation (2.2%) and 3 (6.7%) minor leakages after tube withdrawal (treated conservatively). One death occurred in the stoma group. In the subgroup analysis of CD patients, lower rates of ALs and abdominal abscesses were observed in the T-E group than in the non-T-E and stoma subgroups, but the differences were not significant. CONCLUSIONS: T-E seems to be a safe and feasible operative method for the protection of high-risk intestinal anastomosis, can be reversed and can provide enteral feeding with acceptable tube-related complications. Further studies are needed to validate the role of T-E.


Asunto(s)
Fuga Anastomótica , Enterostomía , Anastomosis Quirúrgica/efectos adversos , Fuga Anastomótica/epidemiología , Fuga Anastomótica/etiología , Fuga Anastomótica/prevención & control , Humanos , Proyectos Piloto , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos
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