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1.
Environ Sci Technol ; 58(3): 1752-1762, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38190653

ABSTRACT

The widespread presence of formaldehyde (HCHO) pollutant has aroused significant environmental and health concerns. The catalytic oxidation of HCHO into CO2 and H2O at ambient temperature is regarded as one of the most efficacious and environmentally friendly approaches; to achieve this, however, accelerating the intermediate formate species formation and decomposition remains an ongoing obstacle. Herein, a unique tandem catalytic system with outstanding performance in low-temperature HCHO oxidation is proposed on well-structured Pd/Mn3O4-MnO catalysts possessing bifunctional catalytic centers. Notably, the optimized tandem catalyst achieves complete oxidation of 100 ppm of HCHO at just 18 °C, much better than the Pd/Mn3O4 (30%) and Pd/MnO (27%) counterparts as well as other physical tandem catalysts. The operando analyses and physical tandem investigations reveal that HCHO is primarily activated to gaseous HCOOH on the surface of Pd/Mn3O4 and subsequently converted to H2CO3 on the Pd/MnO component for deep decomposition. Theoretical studies disclose that Pd/Mn3O4 exhibits a favorable reaction energy barrier for the HCHO → HCOOH step compared to Pd/MnO; while conversely, the HCOOH → H2CO3 step is more facilely accomplished over Pd/MnO. Furthermore, the nanoscale intimacy between two components enhances the mobility of lattice oxygen, thereby facilitating interfacial reconstruction and promoting interaction between active sites of Pd/Mn3O4 and Pd/MnO in local vicinity, which further benefits sustained HCHO tandem catalytic oxidation. The tandem catalysis demonstrated in this work provides a generalizable platform for the future design of well-defined functional catalysts for oxidation reactions.


Subject(s)
Formaldehyde , Palladium , Temperature , Catalytic Domain , Oxidation-Reduction , Catalysis , Palladium/chemistry
2.
Environ Sci Technol ; 58(26): 11760-11770, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38900969

ABSTRACT

Oxygenated volatile organic compounds (OVOCs), emitted in large quantities by the chemical industry, are a major contributor to the formation of ozone and subsequent particulate matter. For the efficient catalytic oxidation of OVOCs, the challenges of molecular activation and intermediate inhibition remain. The construction of bifunctional active sites with specific structures offers a promising way to overcome these problems. Here, the Pd@Layered-CoOx/MFI bifunctional catalyst with core-shell active sites was rationally fabricated though a two-step ligand pyrolysis method, which exhibits a superb oxidation efficiency toward ethyl acetate (EA). Over this, 13.4% of EA (1000 ppm) can be oxidized at just 140 °C with a reaction rate of 13.85 mmol·gPd-1·s-1, around 176.7 times higher than that of the conventional Pd-CoOx/MFI catalyst. The electronic coupling of the Pd-Co pair promotes the electron back-donation from Pd nanoparticles to the layered CoOx shell and facilitates the formation of Pd2+ species, which greatly enhances the adsorption and activation of the electron-rich C═O bond of the EA molecules. In addition, the synergy of these core-shell Pd@Layered-CoOx sites accelerates the activation and transformation of *O species, which inhibit the formation of acetaldehyde and ethanol byproducts, ensuring the rapid total oxidation of EA molecules via the Mars-van Krevelen mechanism. This work established a solid foundation for exploring robust bifunctional catalysts for deep OVOC purification.


Subject(s)
Oxidation-Reduction , Catalysis , Palladium/chemistry , Volatile Organic Compounds/chemistry , Acetates/chemistry
3.
Chemistry ; 29(63): e202302499, 2023 Nov 13.
Article in English | MEDLINE | ID: mdl-37584901

ABSTRACT

Spacious M4 L6 tetrahedra can act as catalytic inhibitors for base-mediated reactions. Upon adding only 5 % of a self-assembled Fe4 L6 cage complex, the conversion of the conjugate addition between ethylcyanoacetate and ß-nitrostyrene catalyzed by proton sponge can be reduced from 83 % after 75 mins at ambient temperature to <1 % under identical conditions. The mechanism of the catalytic inhibition is unusual: the octacationic Fe4 L6 cage increases the acidity of exogenous water in the acetonitrile reaction solvent by favorably binding the conjugate acid of the basic catalyst. The inhibition only occurs for Fe4 L6 hosts with spacious internal cavities: minimal inhibition is seen with smaller tetrahedra or Fe2 L3 helicates. The surprising tendency of the cationic cage to preferentially bind protonated, cationic ammonium guests is quantified via the comprehensive modeling of spectrophotometric titration datasets.

4.
Environ Sci Technol ; 56(22): 16189-16199, 2022 11 15.
Article in English | MEDLINE | ID: mdl-36214785

ABSTRACT

Volatile organic amines are a category of typical volatile organic compounds (VOCs) extensively presented in industrial exhausts causing serious harm to the atmospheric environment and human health. Monometallic Pd and Cu-based catalysts are commonly adopted for catalytic destruction of hazardous organic amines, but their applications are greatly limited by the inevitable production of toxic amide and NOx byproducts and inferior low-temperature activity. Here, a CuO/Pd@SiO2 core-shell-structured catalyst with diverse functionalized active sites was creatively developed, which realized the total decomposition of n-butylamine at 260 °C with a CO2 yield and N2 selectivity reaching up to 100% and 98.3%, respectively (obviously better than those of Pd@SiO2 and CuO/SiO2), owing to the synergy of isolated Pd and Cu sites in independent mineralization of n-butylamine and generation of N2, respectively. The formation of amide and short-chain aliphatic hydrocarbon intermediates via C-C bond cleavage tended to occur over Pd sites, while the C-N bond was prone to breakage over Cu sites, generating NH2· species and long free-N chain intermediates at low temperatures, avoiding the production of hazardous amide and NOx. The SiO2 channel collapse and H+ site production resulted in the formation of N2O via suppressing NH2· diffusion. This work provides critical guidance for a rational fabrication of catalysts with high activity and N2 selectivity for environmentally friendly destruction of nitrogen-containing VOCs.


Subject(s)
Butylamines , Silicon Dioxide , Humans , Silicon Dioxide/chemistry , Catalytic Domain , Amides
5.
Angew Chem Int Ed Engl ; 61(28): e202200763, 2022 Jul 11.
Article in English | MEDLINE | ID: mdl-35347821

ABSTRACT

The development of highly active single-atom catalysts (SACs) and identifying their intrinsic active sites in oxidizing industrial hazardous hydrocarbons are challenging prospects. Tuning the electronic metal-support interactions (EMSIs) is valid for modulating the catalytic performance of SACs. We propose that the modulation of the EMSIs in a Pt1 -CuO SAC significantly promotes the activity of the catalyst in acetone oxidation. The EMSIs promote charge redistribution through the unified Pt-O-Cu moieties, which modulates the d-band structure of atomic Pt sites, and strengthens the adsorption and activation of reactants. The positively charged Pt atoms are superior for activating acetone at low temperatures, and the stretched Cu-O bonds facilitate the activation of lattice oxygen atoms to participate in subsequent oxidation. We believe that this work will guide researchers to engineer efficient SACs for application in hydrocarbon oxidation reactions.

6.
J Environ Sci (China) ; 91: 237-245, 2020 May.
Article in English | MEDLINE | ID: mdl-32172973

ABSTRACT

CuSO4/TiO2 catalysts with high catalytic activity and excellent resistant to SO2 and H2O, were thought to be promising catalysts used in Selective catalytic reduction of nitrogen oxides by NH3. The performance of catalysts is largely affected by calcination temperature. Here, effects of calcination temperature on physicochemical property and catalytic activity of CuSO4/TiO2 catalysts were investigated in depth. Catalyst samples calcined at different temperatures were prepared first and then physicochemical properties of the catalyst were characterized by N2 adsorption-desorption, X-ray diffraction, thermogravimetric analysis, Raman spectra, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, temperature-programmed desorption of NH3, temperature-programmed reduction of H2 and in situ diffuse reflectance infrared Fourier transform spectroscopy. Results revealed that high calcination temperature had three main effects on the catalyst. First, sintering and anatase transform into rutile with increase of calcination temperature, causing a decrement of specific surface area. Second, decomposition of CuSO4 under higher calcination temperature, resulting in disappears of Brønsted acid sites (S-OH), which had an adverse effect on surface acidity. Third, CuO from the decomposition of CuSO4 changed surface reducibility of the catalyst and favored the process of NH3 oxidation to nitrogen oxides (NOx). Thus, catalytic activity of the catalyst calcined under high temperatures (≥600°C) decreased largely.


Subject(s)
Ammonia , Titanium , Catalysis , Oxidation-Reduction , Temperature
7.
Biochem Biophys Res Commun ; 511(3): 650-657, 2019 04 09.
Article in English | MEDLINE | ID: mdl-30826058

ABSTRACT

Although vascular endothelial growth factor (VEGF) promotes vascular permeability and results in edema, studies have suggested it may protect the lung from inflammatory injury via poorly understood mechanisms. Using a mouse model of extracorporeal circulation (ECC), we found that levels of intravenous VEGF increased in lung tissue and inhibited inflammation, thereby attenuating lung injury. These effects could be obtained by intravenous injection or inhalation of VEGF, and they were abolished by treatment with anti-VEGF antibody. Detailed analyses using immunofluorescence and flow cytometry showed that VEGF increased the homing of CD133+ VEGFR1+ progenitors to lung tissue, and this homing could be mimicked in a dose-dependent manner by treatment with VEGF receptor 1 (VEGFR1) agonist and blocked by treatment with anti-VEGFR1 antibody. Interestingly, we found that exposing pulmonary monocytes in vitro to VEGF did not inhibit ECC-induced inflammation. Our results suggest that VEGF enters lung tissues from the circulation and that it attenuates lung injury not by directly inhibiting release of pro-inflammatory factors but by binding to VEGFR1 to recruit CD133+ progenitors. These progenitors then inhibit local inflammation.


Subject(s)
AC133 Antigen/immunology , Lung Injury/immunology , Pneumonia/immunology , Stem Cells/immunology , Vascular Endothelial Growth Factor A/immunology , Vascular Endothelial Growth Factor Receptor-1/immunology , Animals , Lung Injury/complications , Lung Injury/pathology , Male , Mice, Inbred C57BL , Pneumonia/complications , Pneumonia/pathology
8.
J Org Chem ; 84(18): 12157-12164, 2019 09 20.
Article in English | MEDLINE | ID: mdl-31433177

ABSTRACT

Described is an iterative assembly of nitrile oxides and ynamides for the synthesis of isoxazoles and pyrroles. The nitrile oxides could undergo Cu(I)-free cyclization with terminal ynamides for accessing isoxazoles, which could engage in another cyclization with internal ynamides in the presence of Au(I) catalyst to deliver pyrroles, and the reaction could be carried out in a two-step, one-pot procedure. This process is featured with mild reaction condition and broad substrate scope for the synthesis of heterocycles.

9.
Bioorg Med Chem Lett ; 29(7): 912-916, 2019 04 01.
Article in English | MEDLINE | ID: mdl-30777610

ABSTRACT

A new series of 3,6-diaryl-1H-pyrazolo[3,4-b]pyridine compounds have been discovered as potent anaplastic lymphoma kinase (ALK) inhibitors. The 4-hydroxyphenyl in the 6-position of 1H-pyrazolo[3,4-b]pyridine were crucial and a fluorine atom substitution could give promising inhibitory activity. The IC50 of compound 9v against ALK was up to 1.58 nM and a binding mechanism was proposed.


Subject(s)
Anaplastic Lymphoma Kinase/antagonists & inhibitors , Antineoplastic Agents/pharmacology , Pyridines/pharmacology , Antineoplastic Agents/chemistry , Cell Line, Tumor , Humans , Protein Binding , Pyridines/chemistry
10.
Inorg Chem ; 58(4): 2717-2728, 2019 Feb 18.
Article in English | MEDLINE | ID: mdl-30720271

ABSTRACT

In the present work, a series of MOF-74 (Ni) materials with narrow micropore channels and abundant unsaturated metal sites was respectively prepared via hydrothermal (HT), condensation reflux (CE), and microwave-assisted (MW) methods. The physicochemical properties of synthesized materials were characterized by powder X-ray diffraction, N2-sorption, field-emission scanning electron microscopy, Fourier-transform infrared (FTIR), thermogravimetric (TG)/TG-FTIR, X-ray photoelectron spectroscopy, UV-vis-near infrared, NH3/CO2-temperature programmed desorption, and in situ diffuse reflectance infrared Fourier transform spectroscopy. Their CO2/N2 adsorption performances were evaluated by isotherm adsorption and dynamic adsorption experiments. We found that the MW is a rapid and facile protocol for the synthesis of MOF-74 (Ni) materials with highly efficient CO2 capture capacity. The well-shaped MW-140 adsorbent with superior CO2 adsorption capacity of 5.22 mmol/g at 25 °C can be obtained within 60 min by the MW process, almost 6 times higher than that of the commercial activated carbon (0.89 mmol/g). Results of dynamic adsorption experiments showed that the MW-140 material possesses the highest CO2 adsorption capacity of 3.37 mmol/g under humid conditions (RH = 90%). Importantly, MW-140 has excellent adsorption stability and recyclability, superior CO2 capture selectivity (CO2/N2 = 31), and appropriate isosteric heat in CO2 adsorption (21-38 kJ/mol), making it a promising and potential material for industrial CO2 capture. Characterization results demonstrated that the high capture capability of MOF-74 (Ni) materials can be attributed to the synergistic effect of abundant narrow micropore channels and rich five-coordinated Ni2+ open metal sites which are beneficial for the trapping of CO2 molecules.

11.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(4): 660-664, 2018 Jul.
Article in Zh | MEDLINE | ID: mdl-30378325

ABSTRACT

OBJECTIVE: To determine the effect of tranexamic acid (TXA) after cardiopulmonary bypass (CPB) on the outcomes of cardiac surgery patients. METHODS: This retrospective study included adult patients (≥18 years old) who underwent elective valve replace surgery and/or coronary artery bypass surgery (CABG) with CPB from July 1, 2011 to December 31, 2016 in West China Hospital of Sichuan University. The patients were divided into TXA group (n=2 062), who received TXA after CPB, and the control group (n=4 236), who did not receive any TXA at all. The differences in postoperative complications such as death, excessive bleeding, ischemic event and bleeding related event, ICU and hospitality duration of the two groups were analyzed. Logistic regression analysis was performed to examine the effects of TXA on the outcomes of the patients. RESULTS: The rate of excessive bleeding and the median chest tube drainage of TXA group were less than those of control group (P<0.05), while the incidences of death, ischemic event and bleeding related event were comparable between the two groups (P>0.05). Multivariable regression analysis showed TXA after CPB was associated with the reduced risks of excessive bleeding [odds ratio (OR):0.55, 95%confidence interval (CI):0.49-0.62, P<0.001] and death (OR: 0.55, 95%CI:0.30-0.98, P=0.044), but was not associated with ischemic event and bleeding related event. CONCLUSION: TXA after CPB following cardiac surgery could reduce the risk of excessive bleeding and death without increase of ischemic event.


Subject(s)
Antifibrinolytic Agents/therapeutic use , Cardiopulmonary Bypass , Hemorrhage/drug therapy , Tranexamic Acid/therapeutic use , Adult , China , Hemorrhage/prevention & control , Humans , Retrospective Studies , Treatment Outcome
12.
Environ Sci Technol ; 51(11): 6288-6297, 2017 Jun 06.
Article in English | MEDLINE | ID: mdl-28467843

ABSTRACT

Mn3O4, FeMnOx, and FeOx catalysts synthesized via a solvothermal method were employed for catalytic oxidation of methyl-ethyl-ketone (MEK) at low temperature. Mn3O4 with sphere-like morphology exhibited the highest activity for MEK oxidation, over which MEK was completely oxidized to CO2 at 200 °C, and this result can be comparable to typical noble metal loaded catalysts. The activation energy of MEK over Mn3O4 (30.8 kJ/mol) was much lower than that of FeMnOx (41.5 kJ/mol) and FeOx (47.8 kJ/mol). The dominant planes, surface manganese species ratio, surface-absorbed oxygen, and redox capability played important roles in the catalytic activities of catalysts, while no significant correlation was found between specific surface area and MEK removal efficiency. Mn3O4 showed the highest activity, accounting for abundant oxygen vacancies, low content of surface Mn4+ and strong reducibility. The oxidation of MEK to CO2 via an intermediate of diacetyl is a reaction pathway on Mn3O4 catalyst. Due to high efficiency and low cost, sphere-shaped Mn3O4 is a promising catalyst for VOCs abatement.


Subject(s)
Manganese Compounds , Oxides , Temperature , Catalysis , Oxidation-Reduction , Water Purification
13.
Am J Emerg Med ; 32(1): 50-4, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24210889

ABSTRACT

OBJECTIVE: The latest guidelines both increased the requirements of chest compression rate and depth during cardiopulmonary resuscitation (CPR), which may make it more difficult for the rescuer to provide high-quality chest compression. In this study, we investigated the quality of chest compressions during compression-only CPR under the latest 2010 American Heart Association (AHA) guidelines (AHA 2010) and its effect on rescuer fatigue. METHODS: Eighty-six undergraduate volunteers were randomly assigned to perform CPR according to the 2005 AHA guidelines (AHA 2005) or AHA 2010. After the training course and theoretical examination of basic life support, eight min of compression-only CPR performance was assessed. The quality of chest compressions including rate and depth of compression was analyzed. The rescuer fatigue was evaluated by the changes of heart rate and blood lactate, and rating of perceived exertion. RESULTS: Thirty-nine participants in the AHA 2005 group and 42 participants in the AHA 2010 group completed the study. Significantly greater mean chest compression depth and compression rate were both achieved in the AHA 2010 group than in the AHA 2005 group. And significantly greater rescuer fatigue was observed in the AHA 2010 group. In addition, the female in the AHA 2010 group could perform the compression rate required by the guidelines, however, significantly shallower compression depth and greater rescuer fatigue were observed when compared to the male. CONCLUSIONS: The quality of chest compressions was significantly improved following the 2010 AHA guidelines, however, it's more difficult for the rescuer to meet the guidelines due to the increased fatigue of rescuer.


Subject(s)
Cardiopulmonary Resuscitation , Heart Massage , Practice Guidelines as Topic , Cardiopulmonary Resuscitation/methods , Cardiopulmonary Resuscitation/standards , Cardiopulmonary Resuscitation/statistics & numerical data , Female , Heart Massage/standards , Heart Massage/statistics & numerical data , Heart Rate , Humans , Lactic Acid/blood , Male , Muscle Fatigue/physiology , Practice Guidelines as Topic/standards , Young Adult
14.
Gene ; 855: 147114, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36526122

ABSTRACT

BACKGROUND: Glioblastomas (GBMs) are the most lethal brain cancer with a median survival rate of fewer than 15 months. Both clinical and biological features of GBMs are largely different from those of low-grade gliomas (LGs), but the reasons for this intratumoral heterogeneity are not entirely clear. Transfer RNA (tRNA)-derived small RNAs (tsRNAs) were derived from tRNA precursors and mature tRNA, referring to the specific cleavage of tRNAs by dicer and angiogenin (ANG) in particular cells or tissues or under certain conditions such as stress and hypoxia. With the characteristics of wide expression and high stability, tsRNAs could be used as favorable biomarkers for diagnosis, treatment, and prognosis prediction of the tumor, viral infection, neurological as well as other systemic diseases. In this study, we have compared the differential expressed tsRNAs between GBMs and LGs, so as to investigate the possible pathogenic molecules and provide references for discovering novel nucleic acid drugs in future studies. METHODS: Fresh tumor tissues of patients that were diagnosed as GBMs (4 cases) and LGs (5 cases) at the First Affiliated Hospital of Wenzhou Medical University from 2019.05 to 2021.01 were collected. The tsRNAs' levels were analyzed and compared through high-throughput sequencing, candidate tsRNAs were chosen according to the expression level, and the expression of the candidate tsRNAs was validated through qPCR. Finally, the potential targets were imputed using the Miranda and TargetScan databases, and possible biological functions of the differentially expressed (DE) tsRNAs' targets were enriched based on GO and KEGG databases. RESULTS: A total of 4 GBMs and 5 LGs patients were enrolled in the current study. High-throughput sequencing showed that 186 tsRNAs were expressed in two groups, over them, 43 tsRNAs were unique to GBMs, and 24 tsRNAs were unique to LGs. A total of 9 tsRNAs were selected as candidate tsRNAs according to the tsRNA expression level, among which 6 tsRNAs were highly expressed in GBMs and 3 tsRNAs were low expressed in GBMs. qPCR verification further demonstrated that 5 tsRNAs were significantly up-regulated and 1 tsRNA was significantly down-regulated in GBMs: tRF-1-32-chrM.Lys-TTT (p=0.00118), tiRNA-1-33-Gly-GCC-1 (p=0.00203), tiRNA-1-33-Gly-CCC-1 (p=0.00460), tRF-1-31-His-GTG-1 (p=0.00819), tiRNA-1-33-Gly-GCC-2-M3 (p=0.01032), and tiRNA-1-34-Lys-CTT-1-M2 (p=0.03569). Enrichment analysis of the qPCR verified DE tsRNAs showed that the 5 up-regulated tsRNAs seemed to be associated with axon guidance, pluripotent stem cells regulation, nucleotide excision repair, Hippo signaling pathway, and cancer-related pathways, while the down-regulated tsRNA (tRF-1-32-chrM.Lys-TTT) was associated with oocyte meiosis and renin secretion. CONCLUSION: The tsRNAs were differentially expressed in tumor tissues between GBMs and LGs, especially tRF-1-32-chrM.Lys-TTT, tiRNA-1-33-Gly-GCC-1, tiRNA-1-33-Gly-CCC-1, tRF-1-31-His-GTG-1, tiRNA-1-33-Gly-GCC-2-M3, and tiRNA-1-34-Lys-CTT-1-M2. These tsRNAs seemed to be associated with nucleotide excision repair, Hippo signaling, and cancer-related pathways. This may be the main reason for the differences in clinical characteristics between GBMs and LGs, which may provide a certain theoretical basis for further functional research and development of related nucleic acid drugs. CONCLUSION: The tsRNAs were differentially expressed in tumor tissues between GBMs and LGs, especially tRF-1-32-chrM.Lys-TTT, tiRNA-1-33-Gly-GCC-1, tiRNA-1-33-Gly-CCC-1, tRF-1-31-His-GTG-1, tiRNA-1-33-Gly-GCC-2-M3, and tiRNA-1-34-Lys-CTT-1-M2. These tsRNAs seemed to be associated with nucleotide excision repair, Hippo signaling, and cancer-related pathways. This may be the main reason for the differences in clinical characteristics between GBMs and LGs, which may provide a certain theoretical basis for further functional research and development of related nucleic acid drugs.


Subject(s)
Glioblastoma , Glioma , Humans , Glioblastoma/genetics , RNA, Transfer/genetics , Glioma/genetics , High-Throughput Nucleotide Sequencing , RNA Precursors
15.
J Cell Mol Med ; 16(12): 2935-49, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22862802

ABSTRACT

Mesenchymal stem cells (MSCs) have been shown to improve the outcome of acute renal injury models; but whether MSCs can delay renal failure in chronic kidney disease (CKD) remains unclear. In the present study, the were cultured in media containing various concentrations of basic fibroblast growth factor, epidermal growth factor and ascorbic acid 2-phosphate to investigate whether hepatocyte growth factor (HGF) secretion could be increased by the stimulation of these growth factors. Then, TGF-ß1-treated renal interstitial fibroblast (NRK-49F), renal proximal tubular cells (NRK-52E) and podocytes were co-cultured with conditioned MSCs in the absence or presence of ascorbic acid 2-phosphate to quantify the protective effects of conditioned MSCs on renal cells. Moreover, male Sprague-Dawley rats were treated with 1 × 10(6) conditioned MSCs immediately after 5/6 nephrectomy and every other week through the tail vein for 14 weeks. It was found that basic fibroblast growth factor, epidermal growth factor and ascorbic acid 2-phosphate promoted HGF secretion in MSCs. Besides, conditioned MSCs were found to be protective against TGF-ß1 induced epithelial-to-mesenchymal transition of NRK-52E and activation of NRK-49F cells. Furthermore, conditioned MSCs protected podocytes from TGF-ß1-induced loss of synaptopodin, fibronectin induction, cell death and apoptosis. Rats transplanted with conditioned human MSCs had a significantly increase in creatinine clearance rate, decrease in glomerulosclerosis, interstitial fibrosis and increase in CD4(+)CD25(+)Foxp3(+) regulatory T cells counts in splenocytes. Together, our studies indicated that conditioned MSCs preserve renal function by their anti-fibrotic and anti-inflammatory effects. Transplantation of conditioned MSCs may be useful in treating CKD.


Subject(s)
Epithelial-Mesenchymal Transition , Hepatocyte Growth Factor/metabolism , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/physiology , Renal Insufficiency, Chronic/physiopathology , Renal Insufficiency, Chronic/therapy , Animals , Apoptosis , Ascorbic Acid/analogs & derivatives , Ascorbic Acid/metabolism , CD4-Positive T-Lymphocytes/immunology , Cells, Cultured , Coculture Techniques , Creatinine/metabolism , Disease Progression , Epidermal Growth Factor/metabolism , Female , Fibroblast Growth Factor 2/metabolism , Fibronectins/biosynthesis , Fibrosis , Glomerulosclerosis, Focal Segmental , Humans , Kidney/cytology , Kidney/metabolism , Kidney Tubules, Proximal/cytology , Lymphocyte Count , Male , Mesenchymal Stem Cells/metabolism , Microfilament Proteins/deficiency , Middle Aged , Nephrectomy , Podocytes/cytology , Rats , Rats, Sprague-Dawley , Renal Insufficiency, Chronic/metabolism , Transforming Growth Factor beta1/metabolism , Young Adult
16.
J Biol Chem ; 286(46): 39945-57, 2011 Nov 18.
Article in English | MEDLINE | ID: mdl-21930711

ABSTRACT

We have shown previously that the ubiquitin ligase MID1, mutations of which cause the midline malformation Opitz BBB/G syndrome (OS), serves as scaffold for a microtubule-associated protein complex that regulates protein phosphatase 2A (PP2A) activity in a ubiquitin-dependent manner. Here, we show that the MID1 protein complex associates with mRNAs via a purine-rich sequence motif called MIDAS (MID1 association sequence) and thereby increases stability and translational efficiency of these mRNAs. Strikingly, inclusion of multiple copies of the MIDAS motif into mammalian mRNAs increases production of the encoded proteins up to 20-fold. Mutated MID1, as found in OS patients, loses its influence on MIDAS-containing mRNAs, suggesting that the malformations in OS patients could be caused by failures in the regulation of cytoskeleton-bound protein translation. This is supported by the observation that the majority of mRNAs that carry MIDAS motifs is involved in developmental processes and/or energy homeostasis. Further analysis of one of the proteins encoded by a MIDAS-containing mRNA, namely PDPK-1 (3-phosphoinositide dependent protein kinase-1), which is an important regulator of mammalian target of rapamycin/PP2A signaling, showed that PDPK-1 protein synthesis is significantly reduced in cells from an OS patient compared with an age-matched control and can be rescued by functional MID1. Together, our data uncover a novel messenger ribonucleoprotein complex that regulates microtubule-associated protein translation. They suggest a novel mechanism underlying OS and point at an enormous potential of the MIDAS motif to increase the efficiency of biotechnological protein production in mammalian cells.


Subject(s)
Microtubule Proteins/metabolism , Nuclear Proteins/metabolism , Protein Biosynthesis , Protein Serine-Threonine Kinases/biosynthesis , RNA, Messenger/metabolism , RNA-Binding Proteins/metabolism , Transcription Factors/metabolism , Ubiquitin-Protein Ligases/metabolism , 3-Phosphoinositide-Dependent Protein Kinases , Esophagus/abnormalities , Esophagus/metabolism , HeLa Cells , Humans , Hypertelorism/genetics , Hypertelorism/metabolism , Hypospadias/genetics , Hypospadias/metabolism , Microtubule Proteins/genetics , Nuclear Proteins/genetics , Protein Serine-Threonine Kinases/genetics , RNA, Messenger/genetics , RNA-Binding Proteins/genetics , Transcription Factors/genetics , Ubiquitin-Protein Ligases/genetics
18.
Gen Thorac Cardiovasc Surg ; 70(4): 337-346, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34561761

ABSTRACT

OBJECTIVE: To evaluate the effects of administering tranexamic acid (TXA) after cardiopulmonary bypass, instead of after anesthesia induction, on postoperative seizures and blood transfusion requirements. METHODS: Adult patients who underwent valve surgery and/or coronary artery bypass grafting at West China Hospital between July 1, 2011 and December 31, 2016 were retrospectively analyzed. Patients either received TXA after bypass (n = 2062) or not (n = 4236). Logistic regression and propensity score matching analysis were performed to assess effects of TXA on postoperative seizures and blood product requirements in hospital. RESULTS: Among 6298 patients, seizures occurred in 2.4% (102/4236) in the no-TXA group and 2.7% (56/2062) in the TXA group (P = 0.46). The number of patients receiving any blood products was greater in the no-TXA group (57.3%, 2428/4236) than in the TXA group (53.1%, 1095/2062) (P < 0.01), and the volume of blood products was also greater in the no-TXA group (1.5 vs. 1.0 units, P < 0.01). TXA was not associated with increased incidence of postoperative seizures (adjusted OR 1.16, 95% CI 0.83-1.62) but was associated with lower incidence of a requirement for blood products (adjusted OR 0.82, 95% CI 0.73-0.92). Similar results were obtained after patients from the two groups were matched based on propensity scoring. TXA was associated with reduced requirements for fresh frozen plasma, platelets and cryoprecipitate, but not red blood cells. CONCLUSIONS: Administering TXA after bypass may reduce requirements for blood products without increasing risk of seizures following cardiac surgery.


Subject(s)
Antifibrinolytic Agents , Tranexamic Acid , Adult , Antifibrinolytic Agents/adverse effects , Blood Loss, Surgical/prevention & control , Cardiopulmonary Bypass/adverse effects , Humans , Retrospective Studies , Seizures/chemically induced , Seizures/epidemiology , Tranexamic Acid/adverse effects
19.
J Healthc Eng ; 2022: 6033989, 2022.
Article in English | MEDLINE | ID: mdl-35340255

ABSTRACT

Objective: Systematic analysis of the incidence of percutaneous spinal endoscopic technique and traditional open surgery for lumbar disc herniation. Methods: A randomized controlled trial (RCT) and cohort study on complications related to traditional open surgery was searched on the MEDLINE, Cochrane Library, PubMed, Web of Science, Chinese journal full-text database (CNKI), Wanfang, and Embase database. Language is not limited. The quality of each study was evaluated, various complications were compiled into electronic baseline tables, and the data from these studies were available. Meta-analysis and synthesis were performed with the RevMan 5.3 software to evaluate the statistical significance of both surgical techniques in terms of various complications. Results: 12 studies were eventually included, and a total of 2,797 patients were included in the analysis. Meta-analysis results showed that there was no statistical difference in postoperative paresthesia between percutaneous spinal endoscopy and traditional open surgery (OR = 1.17, 95% CI (0.82, 1.66), P = 0.38, I 2 = 0%, Z = 0.88), direct nerve root damage (OR = 0.79, 95% CI (0.58, 1.07), P = 0.13, I 2 = 73%, Z = 1.52), and intraoperative hemorrhage and hematoma formation (OR = 1.00, 95% CI (0.67, 1.48), P = 0.99, I 2 = 0%, Z = 0.02), but there was a statistical difference in disc recurrence (OR = 2.24, 95% CI (1.56, 3.21), P < 0.0001, I 2 = 81%, Z = 4.39). Conclusion: Compared with the traditional open surgical treatment of lumbar disc herniation, percutaneous spinal endoscopic technology has obvious advantages in reducing nerve root injury, dural injury, and surgical area wound complications, but it is limited to preventing the technical characteristics of the surgical site, which is worse than that of open surgery.


Subject(s)
Diskectomy, Percutaneous , Intervertebral Disc Displacement , Diskectomy, Percutaneous/methods , Endoscopy/adverse effects , Endoscopy/methods , Humans , Intervertebral Disc Displacement/surgery , Lumbar Vertebrae/surgery , Randomized Controlled Trials as Topic , Treatment Outcome
20.
PLoS One ; 17(5): e0268571, 2022.
Article in English | MEDLINE | ID: mdl-35617238

ABSTRACT

Pulmonary ischemia and reperfusion (I/R) injury occurs in many clinical conditions and causes severe damage to the lungs. Diabetes mellitus (DM) predisposes to pulmonary I/R injury. We previously found that remote liver ischemia preconditioning protected lungs against pulmonary I/R injury. The aim of the present study was to investigate whether remote liver ischemic postconditioning (RLIPost) attenuates pulmonary damage induced by I/R injury in non-diabetic or diabetic rats. Male Sprague-Dawley rats were assigned into non-diabetic and diabetic groups. All rats except for the sham were exposed to 45 min of left hilum occlusion followed by 2 h of reperfusion. RLIPost was conducted at the onset of pulmonary reperfusion by four cycles of 5 min of liver ischemia and reperfusion. Lung injury was assessed by the wet/dry weight ratio, pulmonary oxygenation, histopathological changes, apoptosis and the expression of inflammatory cytokines. Reperfusion-associated protein phosphorylation states were determined. RLIPost offered strong pulmonary-protection in both non-diabetic and diabetic rats, as reflected in reduced water content and pulmonary structural damage, recovery of lung function, inhibition of apoptosis and inflammation after ischemia-reperfusion. RLIPost induced the activation of pulmonary STAT-3, a key component in the SAFE pathway, but not activation of the proteins in the RISK pathway, in non-diabetic rats. In contrast, RLIPost-induced pulmonary protection in diabetic lungs was independent of SAFE or RISK pathway activation. These results demonstrate that RLIPost exerts pulmonary protection against I/R-induced lung injury in non-diabetic and diabetic rats. The underlying mechanism for protection may be different in non-diabetic (STAT-3 dependent) versus diabetic (STAT-3 independent) rats.


Subject(s)
Diabetes Mellitus, Experimental , Ischemic Postconditioning , Ischemic Preconditioning , Lung Injury , Reperfusion Injury , Animals , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/pathology , Ischemic Postconditioning/methods , Ischemic Preconditioning/methods , Liver/metabolism , Lung/pathology , Lung Injury/etiology , Lung Injury/pathology , Lung Injury/prevention & control , Male , Rats , Rats, Sprague-Dawley , Reperfusion Injury/complications , Reperfusion Injury/metabolism , Reperfusion Injury/prevention & control
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