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1.
Int J Biol Sci ; 20(6): 2008-2026, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38617548

RESUMEN

Renal aging may lead to fibrosis and dysfunction, yet underlying mechanisms remain unclear. We explored whether deficiency of the Polycomb protein Bmi1 causes renal aging via DNA damage response (DDR) activation, inducing renal tubular epithelial cell (RTEC) senescence and epithelial-mesenchymal transition (EMT). Bmi1 knockout mice exhibited oxidative stress, DDR activation, RTEC senescence, senescence-associated secretory phenotype (SASP), and age-related fibrosis in kidneys. Bmi1 deficiency impaired renal structure and function, increasing serum creatinine/urea, reducing creatinine clearance, and decreasing cortical thickness and glomerular number. However, knockout of the serine-threonine kinase Chk2 alleviated these aging phenotypes. Transcriptomics identified transforming growth factor beta 1 (TGFß1) upregulation in Bmi1-deficient RTECs, but TGFß1 was downregulated upon Chk2 knockout. The tumor suppressor protein p53 transcriptionally activated TGFß1, promoting EMT in RTECs. Bmi1 knockout or oxidative stress (induced with H2O2) increased TGFß1 expression, and EMT in RTECs and was partly reversed by p53 inhibition. Together, Bmi1 deficiency causes oxidative stress and DDR-mediated RTEC senescence/SASP, thus activating p53 and TGFß1 to induce EMT and age-related fibrosis. However, blocking DDR (via Chk2 knockout) or p53 ameliorates these changes. Our study reveals mechanisms whereby Bmi1 preserves renal structure and function during aging by suppressing DDR and p53/TGFß1-mediated EMT. These pathways represent potential targets for detecting and attenuating age-related renal decline.


Asunto(s)
Peróxido de Hidrógeno , Proteína p53 Supresora de Tumor , Animales , Ratones , Envejecimiento , Creatinina , Daño del ADN/genética , Transición Epitelial-Mesenquimal/genética , Riñón , Estrés Oxidativo/genética , Complejo Represivo Polycomb 1/genética , Proteínas Proto-Oncogénicas/genética , Proteína p53 Supresora de Tumor/genética
2.
Front Psychol ; 15: 1362127, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38562234

RESUMEN

Objective: This research intended to assess and compare influence of psychosocial interventions in death anxiety in patients, providing evidence-based guidance for both patients and healthcare providers. Design: The present study exclusively gathered randomized controlled trials by comprehensively searching across multiple databases, comprising of PubMed, Embase, Cochrane Library, Web of Science, and Scopus. The methodological quality of the enrolled studies involved in the analysis was assessed using the Cochrane bias risk assessment tool, and data analysis was performed utilizing appropriate software. Results: This research, encompassing 15 randomized controlled trials with a cumulative sample size of 926 patients, spanned from the earliest possible date to December 2023. The findings of network meta-analysis unveiled that the Rational-Emotive Hospice Care Therapy significantly reduced death anxiety among patients (Sequentially Updated Cumulative Ranking Analysis: 100%). Conclusion: The ranking plot of the network suggested that the rational-emotive hospice care therapy exhibited superior efficacy as a psychological treatment for reducing the death anxiety of patients.Systematic review registration: [https://clinicaltrials.gov/], identifier: [CRD42023484767].

3.
Environ Pollut ; 334: 122208, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37454716

RESUMEN

Co-activation of H2O2 with biochar and iron sources together provides an attractive strategy for efficient removal of refractory pollutants, because it can solve the problems of slow Fe(Ⅱ) regeneration in Fenton/Fenton-like processes and of low •OH yield in biochar-activated process. In this study, a wood-derived biochar (WB) was modified by heteroatom doping for the objective of enhancing its reactivity toward co-activation of H2O2. The performance of the co-activated system using doped biochars and trace dissolved Fe(Ⅲ) on oxidation of organic pollutants was evaluated for the first time. The characterizations using X-ray photoelectron spectroscopy (XPS), Raman spectra and electrochemical analyses indicate that heteroatom doping introduced more defects in biochar and improved its electron transfer capacity. The oxidation experiments show that heteroatom doping improved the performance of biochar in the co-activated process, in which the N,S-codoped biochar (NSB) outperformed the N-doped biochar (NB) on oxidation of pollutants. The reaction rate constant (kobs) for oxidation of sulfadiazine in NSB + Fe + H2O2 is 2.25 times that in NB + Fe + H2O2, and is 72.9 times that in the Fenton-like process without biochar, respectively. The mechanism investigations indicate that heteroatom doping enhanced biochar's reactivity on catalyzing the decomposition of H2O2 and on reduction of Fe(Ⅲ) due to the improved electron transfer/donation capacity. In comparison with N-doping, N,S-codoping provided additional electron donor (thiophenic C-S-C) for faster regeneration of Fe(Ⅱ) with less amount of doping reagent used. Furthermore, co-activation with NSB maintained to be efficient at a milder acidic pH than Fenton/Fenton-like processes, and can be used for oxidation of different pollutants and in real water. Therefore, this research provides a novel, sustainable and cost-efficient method for oxidation of refractory pollutants.


Asunto(s)
Compuestos Férricos , Contaminantes Químicos del Agua , Peróxido de Hidrógeno/química , Contaminantes Químicos del Agua/análisis , Compuestos Ferrosos , Oxidación-Reducción
4.
J Orthop Translat ; 40: 13-26, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37200907

RESUMEN

Background: It has been demonstrated that vitamin D deficiency is associated with an increased risk of patients developing lumbar disc herniation. However, intervertebral disc degeneration caused by active vitamin D deficiency has not been reported. Thus, the purpose of this study was to e investigate the role and mechanism of 1,25-dihydroxyvitamin D (1,25(OH)2D) insufficiency in promoting intervertebral disc degeneration. Methods: The phenotypes of intervertebral discs were compared in wild-type mice and mice with heterozygous deletion of 1α-hydroxylase [1α(OH)ase+/-] at 8 mouths of age using iconography, histology and molecular biology. A mouse model that overexpressed Sirt1 in mesenchymal stem cells on a 1α(OH)ase+/- background (Sirt1Tg/1α(OH)ase+/-) was generated by crossing Prx1-Sirt1 transgenic mice with 1α(OH)ase+/- mice and comparing their intervertebral disc phenotypes with those of Sirt1Tg, 1α(OH)ase+/- and wild-type littermates at 8 months of age. A vitamin D receptor (VDR)-deficient cellular model was generated by knock-down of endogenous VDR using Ad-siVDR transfection into nucleus pulposus cells; VDR-deficient nucleus pulposus cells were then treated with or without resveratrol. The interactions between Sirt1 and acetylated p65, and p65 nuclear localization, were examined using co-immunoprecipitation, Western blots and immunofluorescence staining. VDR-deficient nucleus pulposus cells were also treated with 1,25(OH)2D3, or resveratrol or 1,25(OH)2D3 plus Ex527 (an inhibitor of Sirt1). Effects on Sirt1 expression, cell proliferation, cell senescence, extracellular matrix protein synthesis and degradation, nuclear factor-κB (NF-κB), and expression of inflammatory molecules, were examined, using immunofluorescence staining, Western blots and real-time RT-PCR. Results: 1,25(OH)2D insufficiency accelerated intervertebral disc degeneration by reducing extracellular matrix protein synthesis and enhancing extracellular matrix protein degradation with reduced Sirt1 expression in nucleus pulposus tissues. Overexpression of Sirt1 in MSCs protected against 1,25(OH)2D deficiency-induced intervertebral disc degeneration by decreasing acetylation and phosphorylation of p65 and inhibiting the NF-κB inflammatory pathway. VDR or resveratrol activated Sirt1 to deacetylate p65 and inhibit its nuclear translocation into nucleus pulposus cells. Knockdown of VDR decreased VDR expression and significantly reduced the proliferation and extracellular matrix protein synthesis of nucleus pulposus cells, significantly increased the senescence of nucleus pulposus cells and significantly downregulated Sirt1 expression, and upregulated matrix metallopeptidase 13 (MMP13), tumor necrosis factor-α (TNF-α) and interleukin 1ß (IL-1ß) expression; the ratios of acetylated and phosphorylated p65/p65 in nucleus pulposus cells were also increased. Treatment of nucleus pulposus cells with VDR reduction using 1,25(OH)2D3 or resveratrol partially rescued the degeneration phenotypes, by up-regulating Sirt1 expression and inhibiting NF-κB inflammatory pathway; these effects in nucleus pulposus cells were blocked by inhibition of Sirt1. Conclusion: Results from this study indicate that the 1,25(OH)2D/VDR pathway can prevent the degeneration of nucleus pulposus cells by inhibiting the NF-κB inflammatory pathway mediated by Sirt1.The Translational Potential of This Article: This study provides new insights into the use of 1,25(OH)2D3 to prevent and treat intervertebral disc degeneration caused by vitamin D deficiency.

5.
Stem Cells ; 41(6): 672-683, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37099695

RESUMEN

Bone marrow mesenchymal stem cells (BMSCs) are indispensable cells constituting the bone marrow microenvironment that are generally recognized as being involved in the development and progression of osteosarcoma (OS). To explore whether mTORC2 signaling inhibition in BMSCs suppressed OS growth and tumor-caused bone destruction, 3-month-old littermates genotyped Rictorflox/flox or Prx1-cre; Rictorflox/flox (with same gender) were injected with K7M2 cells in the proximal tibia. After 40 days, bone destruction was alleviated in Prx1-cre; Rictorflox/flox mice, as observed on X-ray and micro-CT. This was accompanied by decreased serum N-terminal propeptide of procollagen type I (PINP) levels and reduced tumor bone formation in vivo. Interactions between K7M2 and BMSCs were studied in vitro. Rictor-deficient BMSCs, which were cultured in tumor-conditioned medium (TCM), caused reduced bone proliferation and suppressed osteogenic differentiation. Moreover, compared with the control group, K7M2 cells cultured in BCM (culture medium extracted from Rictor-deficient BMSCs) displayed less proliferation, migration, and invasion, and attenuated osteogenic activity. Forty types of cytokines were then analyzed by mouse cytokine array and decreased levels CCL2/3/5 and interleukin-16 were detected in Rictor-deficient BMSCs. These results suggested that inhibition of mTORC2 (Rictor) signaling pathway in BMSCs exerted anti-OS effects through 2 mechanisms: (1) by suppressing the proliferation and osteogenic differentiation of BMSCs induced by OS to alleviate bone destruction; (2) by reducing the secretion of cytokines by BMSCs, which are closely related to OS cell growth, migration, invasion, and tumorigenic osteogenesis.


Asunto(s)
Neoplasias Óseas , Células Madre Mesenquimatosas , Osteosarcoma , Ratones , Animales , Osteogénesis , Células Madre Mesenquimatosas/metabolismo , Diferenciación Celular , Células de la Médula Ósea , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo , Citocinas/metabolismo , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Células Cultivadas , Osteosarcoma/metabolismo , Microambiente Tumoral
6.
Bioresour Technol ; 263: 475-482, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29775903

RESUMEN

For the purpose of producing carbons with developed mesoporosity, a wood biochar was thermally treated at 600-800 °C in the air/nitrogen atmosphere. The mesopore development was observed when the air flux increased to 50-90 mL/min, and the carbon product having high mesopore surface area (316 m2/g) and mesopore pore volume (0.284 cm3/g) was produced at the treatment temperature of 700 °C. The mesopores were developed mainly in the temperature holding stage of thermal treatment, with size mainly ranged from 20 to 60 Å. The carbons' adsorption to the antibiotic tetracycline was enhanced by 5.5-9.2 folds when the air/nitrogen mixture was used instead of nitrogen atmosphere in thermal treatment, and the enhanced adsorption is positively related to the mesopore development. In general, this research provides a facile way to produce carbons with developed mesoporosity, so as to improve their adsorption to bulky organic molecules.


Asunto(s)
Carbón Orgánico , Tetraciclina/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Carbono , Nitrógeno
7.
Bioresour Technol ; 241: 908-914, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28629107

RESUMEN

For the purpose of safe disposal of biomass contaminated by biosorption of heavy metals, phosphate-assisted pyrolysis of water hyacinth biomass contaminated by lead (Pb) was tried to reduce the bioavailability and leaching potential of Pb, using direct pyrolysis without additive as a control method. Direct pyrolysis of the contaminated biomass at low temperatures (300 and 400°C) could reduce the bioavailability of Pb, but the leaching potential of Pb was increased with the rising pyrolysis temperature. While phosphate-assisted pyrolysis significantly enhanced the recovery and stability of Pb in the char. Specifically, the percentages of bioavailable Pb and leachable Pb in the chars obtained by phosphate-assisted pyrolysis at low temperatures were reduced to less than 5% and 7%, respectively. The sequential extraction test indicated the transformation of Pb into more stable fractions after phosphate-assisted pyrolysis, which was related to the formation of Pb phosphate minerals including pyromorphite and lead-substituted hydroxyapatite.


Asunto(s)
Eichhornia , Plomo , Contaminantes del Suelo , Disponibilidad Biológica , Biomasa , Hyacinthus , Fosfatos , Eliminación de Residuos Líquidos
8.
Bioresour Technol ; 235: 185-192, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28365346

RESUMEN

Biochars were produced from celery biomass by slow pyrolysis at 350 and 500°C, and featured by high content of alkaline minerals namely salts of alkali and alkaline earth metals. The biochars' efficiency on removing Pb2+ from solution was investigated, and two biochars derived from celery stalk (StC350 and StC500) showed higher Pb2+ sorption capacity (288 and 304mg/g) than most biochars reported previously. The sorption mechanisms involving precipitation, cation exchange and surface complexation are related to three biochar fractions namely water-soluble matter, acid-soluble substances and insoluble organic carbon. The relative contributions of water-soluble matter and acid-soluble substances to the total Pb2+ removal were 59.8% and 36.6% for the StC350 biochar, and 62.8% and 34.9% for the StC500 biochar, respectively. The results indicate that biochars derived from vegetable wastes are potential candidates for efficient sorption of heavy metals.


Asunto(s)
Apium , Carbón Orgánico , Adsorción , Metales Pesados , Minerales , Soluciones
9.
Water Sci Technol ; 75(2): 482-489, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28112675

RESUMEN

The porous biochars have exhibited good adsorption to many organic pollutants, but the relationship between biochars' porosity and their adsorption capacity is not clear at the moment. In this work, six biochars were produced from different feedstocks and under different pyrolysis conditions, and used for adsorption of three neutral herbicides from water. The results demonstrated that the adsorption capacity was dominated by the mesopore (1.7-50 nm) area of biochars, instead of their total surface area, according to the analysis of surface area-normalized adsorption data with both Langmuir model and a mixed adsorption and partition model. The results implied the inaccessibility of most micropores in biochars to the organic molecules with nano-scale molecular dimension, and alkalis in feedstock and an oxygen-containing atmosphere in heat treatment for producing biochars would favor the development of mesopores.


Asunto(s)
Carbón Orgánico/química , Herbicidas/química , Modelos Químicos , Contaminantes Químicos del Agua/química , Adsorción , Herbicidas/análisis , Porosidad , Contaminantes Químicos del Agua/análisis
10.
J Hazard Mater ; 324(Pt B): 464-471, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-27863797

RESUMEN

The remediation of heavy metal-contaminated soil and water using plant biomass is considered to be a green technological approach, although the harmless disposal of biomass accumulated with heavy metals remains a challenge. A potential solution to this problem explored in this work involves combining phosphate pretreatment with pyrolysis. Pb(II) was accumulated in celery biomass with superior sorption capacity and also in ordinary wood biomass through biosorption. The Pb(II)-impregnated biomass was then pretreated with phosphoric acid or calcium dihydrogen phosphate (CaP) and pyrolyzed at 350 or 450°C. Pb(II) from biomass was in turn almost totally retained in chars, and the percentage of DTPA-extractable Pb(II) was reduced to less than 5% of total Pb(II) in chars through CaP pretreatment. Pb(II) stabilization was further confirmed through a sequential extraction test, which showed that more than 95% of Pb(II) was converted into stable species composed mainly of lead phosphates according to X-ray diffraction (XRD) and scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX) analyses. Overall, phosphate-pretreated pyrolysis can stabilize both Pb(II) and degradable biomass, so as to control efficiently the hazards of heavy metal-contaminated biomass.


Asunto(s)
Carbón Orgánico/química , Contaminantes Ambientales/análisis , Restauración y Remediación Ambiental/métodos , Calor , Plomo/análisis , Fosfatos/química , Adsorción , Apium/química , Biomasa , Modelos Teóricos , Madera/química
11.
Environ Sci Pollut Res Int ; 23(19): 19156-63, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27351874

RESUMEN

Biochars' properties will change after application in soil due to the interactions with soil constituents, which would then impact the performance of biochars as soil amendment. For a better understanding on these interactions, two woody biochars of different surface areas (SA) were physically treated with aluminum oxide (Al-oxide) to investigate its potential influence on biochars' sorption property. Both the micropore area and mesopore (17∼500 Å in diameter) area of the low-SA biochar were enhanced by at least 1.5 times after treatment with Al-oxide, whereas the same treatment did not change the surface characteristics of the high-SA biochar due partly to its well-developed porosity. The enhanced sorption of the pesticide isoproturon to the Al-oxide-treated low-SA biochar was observed and is positively related to the increased mesopore area. The desorption hysteresis of pesticide from the low-SA biochar was strengthened because of more pesticide molecules entrapped in the expanded pores by Al-oxide. However, no obvious change of pesticide sorption to the high-SA biochar after Al-oxide treatment was observed, corresponding to its unchanged porosity. The results suggest that the influence of Al-oxide on the biochars' sorption property is dependent on their porosity. This study will provide valuable information on the use of biochars for reducing the bioavailability of pesticides.


Asunto(s)
Carbón Orgánico/química , Modelos Químicos , Plaguicidas/análisis , Contaminantes del Suelo/análisis , Adsorción , Óxido de Aluminio , Herbicidas/análisis , Plaguicidas/química , Compuestos de Fenilurea , Suelo/química , Contaminantes del Suelo/química , Madera/química
12.
J Agric Food Chem ; 60(26): 6463-70, 2012 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-22686323

RESUMEN

The sustained release and reduced leaching of herbicides is expected for enhancing their efficacy and minimizing their pollution. For this purpose, the rice straw biochar made at a relatively low temperature (350 °C) (RS350) was used simultaneously as the carrier for incorporating herbicides besides as the soil amendment. In this way, the sustained release of herbicides acetochlor and 2,4-D was obtained in the release experiments, due to the high and reversible sorption by RS350 biochar. Besides, the RS350 biochar significantly reduced the leached amount of herbicides by 25.4%-40.7% for acetochlor, and by 30.2%-45.5% for 2,4-D, depending on the depth (50 or 100 mm) of biochar-amended soil horizon. The high retention of both herbicides in the biochar-amended topsoil makes it possible to extend their efficacy. The results suggest a potential way of using low temperature biochars to reduce the leaching of herbicides without impacting their efficacy.


Asunto(s)
Carbón Orgánico , Herbicidas/administración & dosificación , Oryza , Suelo/análisis , Ácido 2,4-Diclorofenoxiacético/administración & dosificación , Ácido 2,4-Diclorofenoxiacético/química , Adsorción , Carbón Orgánico/química , Preparaciones de Acción Retardada , Restauración y Remediación Ambiental/métodos , Herbicidas/química , Toluidinas/administración & dosificación , Toluidinas/química
13.
Di Yi Jun Yi Da Xue Xue Bao ; 25(9): 1188-90, 2005 Sep.
Artículo en Chino | MEDLINE | ID: mdl-16174596

RESUMEN

OBJECTIVE: To discuss the indications and other related issues of artificial hip replacement. METHOD: A retrospective analysis was conducted in 37 cases with artificial hip replacement with complete follow-up data treated between 1996 and 2001. RESULTS: The patients were followed up for 1 to 5 years. The average Harris score of these patients was 51 preoperatively and 82 postoperatively, and 10 of them had excellent, 23 good, 2 acceptable and 2 poor outcomes. Such complications as prothesis mobilization (2 cases), joint dislocation (1 case), prothesis pricking through the femur (1 case) and infection (3 cases) occurred after the operation. Embolism in the deep veins of the lower limb, sciatic nerve injury or severe general complications were not observed. CONCLUSION: Proper evaluation of the indications, careful preoperative preparation, proficient operative skills, and good postoperative treatment can ensure favorable outcome of artificial hip replacement with minimum complications.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Fracturas del Cuello Femoral/cirugía , Necrosis de la Cabeza Femoral/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Cadera/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
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