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2.
Polymers (Basel) ; 16(6)2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38543368

RESUMO

Since the discovery of α-diimine catalysts in 1995, an extensive series of Brookhart-type complexes have shown their excellence in catalyzing ethylene polymerizations with remarkable activity and a high molecular weight. However, although this class of palladium complexes has proven proficiency in catalyzing ethylene copolymerization with various polar monomers, the α-diimine nickel catalysts have generally exhibited a much worse performance in these copolymerizations compared to their palladium counterparts. Recently, Brookhart et al. reported a notable exception, demonstrating that α-diimine nickel catalysts could catalyze the ethylene copolymerization with some vinylalkoxysilanes effectively, producing functionalized polyethylene incorporating trialkoxysilane (-Si(OR)3) groups. This breakthrough is significant since Pd-catalyzed copolymerizations are commercially less usable due to the high cost of palladium. Thus, the utilization of Ni, given its abundance in raw materials and cost-effectiveness, is a landmark in ethylene/polar vinyl monomer copolymerization. Inspired by these findings, we used density functional theory (DFT) calculations to investigate the mechanistic study of ethylene copolymerization with vinyltrimethoxysilane (VTMoS) catalyzed by Brookhart-type nickel catalysts, aiming to elucidate the molecular-level understanding of this unique reaction. Initially, the nickel complexes and cationic active species were optimized through DFT calculations. Subsequently, we explored the mechanisms including the chain initiation, chain propagation, and chain termination of ethylene homopolymerization and copolymerization catalyzed by Brookhart-type complexes. Finally, we conducted an energetic analysis of both the in-chain and chain-end of silane enchainment. It was found that chain initiation is the dominant step in the ethylene homopolymerization catalyzed by the α-diimine Ni complex. The 1,2- and 2,1-insertion of vinylalkoxysilane exhibit similar barriers, explaining the fact that both five-membered and four-membered chelates were identified experimentally. After the VTMoS insertion, the barriers of ethylene reinsertion become higher, indicating that this step is the rate-determining step, which could be attributed to the steric hindrance between the incoming ethylene and the bulky silane substrate. We have also reported the energetic analysis of the distribution of polar substrates. The dominant pathway of chain-end -Si(OR)3 incorporation is suggested as chain-walking → ring-opening → ethylene insertion, and the preference of chain-end -Si(OR)3 incorporation is primarily attributed to the steric repulsion between the pre-inserted silane group and the incoming ethylene molecule, reducing the likelihood of in-chain incorporation.

3.
Antioxidants (Basel) ; 13(3)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38539856

RESUMO

Tomato is the vegetable with the largest greenhouse area in China, and low temperature is one of the main factors affecting tomato growth, yield, and quality. Hydrogen sulfide (H2S) plays an important role in regulating plant chilling tolerance, but its downstream cascade reaction and mechanism remain unclear. Mitogen-activated protein kinases (MAPK/MPKs) are closely related to a variety of signaling substances in stress signal transmission. However, whether H2S is related to the MPK cascade pathway in response to low-temperature stress is rarely reported. In this study, NaHS treatment significantly decreased the electrolyte leakage (EL), superoxide anion (O2-) production rate, and hydrogen peroxide (H2O2) content of seedlings at low temperatures. In addition, the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were obviously increased; and the photochemical efficiency of PSII (Fv/Fm) was enhanced with treatment with NaHS, indicating that NaHS improved the seedlings' cold tolerance by alleviating the degree of membrane lipid peroxidation and oxidative damage. However, H2S scavenger hypotaurine (HT) treatment showed the opposite effect. We found that H2S content, L-cysteine desulfhydrase (LCD) activity, and mRNA expression were increased by chilling stress but reduced by MPK inhibitor PD98059; PD98059 reversed the alleviating effect of H2S via increasing the EL and H2O2 contents. The expression levels of MPK1-MPK7 at low temperatures showed that SlMPK4 was significantly induced by exogenous NaHS and showed a trend of first increasing and then decreasing, while the expression level of SlMPK4 in HT-treated seedlings was lower than that of the control. After SlMPK4 was silenced by virus-induced gene silencing, the H2S-induced upregulation of C-repeat-Binding Factor (CBF1), inducer of CBF expression 1 (ICE1), respiratory burst oxidase homologs (RBOH1, RBOH2) at low temperatures disappeared, and tomato cold tolerance decreased. In conclusion, H2S improves the cold tolerance of tomato plants by increasing the activity of antioxidant enzymes and reducing reactive oxygen species (ROS) accumulation and membrane lipid peroxidation. MPK4 may act as a downstream signaling molecule in this process.

4.
Polymers (Basel) ; 16(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38337295

RESUMO

The development of catalysts has significantly advanced the progress of polyolefin materials. In particular, group 4 (Ti, Zr, Hf) non-metallocene catalysts ligated with [N,N] bidentate ligand(s) have garnered increasing attention in the field of olefin polymerization due to their structurally stability and exceptional polymerization behaviors. Ligands containing nitrogen donors are diverse and at the core of many highly active catalysts. They mainly include amidine, guanidinato, diamine, and various N-heterocyclic ligands, which can be used to obtain a series of new polyolefin materials, such as ultrahigh molecular weight polyethylene (UHWMPE), olefin copolymers (ethylene/norbornene and ethylene/α-olefin) with high incorporations, and high isotactic or syndiotactic polypropylene after coordination with group 4 metals and activation by cocatalysts. Herein, we focus on the advancements and applications of this field over the past two decades, and introduce the catalyst precursors with [N,N] ligand(s), involving the effects of ligand structure, cocatalyst selection, and polymerization conditions on the catalytic activity and polymer properties.

6.
Inorg Chem ; 62(14): 5660-5668, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36961829

RESUMO

In comparison with the research of transition-metal-tetrel complexes, the chemistry of lanthanide tetrel complexes, especially for these bearing heavier tetrel element ligands, is still relatively underexplored. In this research, K[Cp3Ln(III)CH2Ph], [(DME)3Li][Cp3Ln(III)GePh3], and [(DME)3Li][Cp3Ln(III)SnPh3] [Ln(III) = La(III), Ce(III)] have been synthesized by reacting [(DME)3Na][Cp3La(µ-Cl)LaCp3] or Cp3Ce(THF) with alkali metal alkyl, germyl, and stannyl reagents. Additionally, [(DME)3Li][Cp3Ce(III)SnPh3] is the first example of Ce(III)-Sn bond containing complex. All the obtained early Ln(III) tetrel ate-complexes were structurally analyzed by single-crystal X-ray diffraction. The formal shortness ratios of the Ln(III)-C, Ln(III)-Ge, and Ln(III)-Sn bonds are in the range of 1.03-1.11. Together with the previously reported [(DME)3Li][Cp3Ln(III)SiPh3], a group of tetrel (up to Sn) lanthanocene ate-complexes with an analogous coordination pattern are presented. Computational studies suggest the strongly polarized nature of the Ln(III)-E (E = C, Si, Ge, Sn) bonds in these complexes, with 77-85% atomic orbital contribution from tetrel elements and 15-23% atomic orbital contribution from Ln(III). The UV-vis measurements of this series of complexes show that the characteristic absorptions are hypsochromically shifted for Ln(III) heavier tetrel complexes in comparison to their lighter congeners. Moreover, the HOMOs, in which the Ln(III)-E σ-bonding orbitals are the dominant components, of these series complexes act as donor orbitals of the major electron transitions, as being disclosed by the time-dependent density functional theory analysis.

7.
Oxid Med Cell Longev ; 2023: 5343746, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36811020

RESUMO

Background: Oxidative stress (OS) can either lead to leukemogenesis or induce tumor cell death by inflammation and immune response accompanying the process of OS through chemotherapy. However, previous studies mainly focus on the level of OS state and the salient factors leading to tumorigenesis and progression of acute myeloid leukemia (AML), and nothing has been done to distinguish the OS-related genes with different functions. Method: First, we downloaded single-cell RNA sequencing (scRNAseq) and bulk RNA sequencing (RNAseq) data from public databases and evaluated the oxidative stress functions between leukemia cells and normal cells by the ssGSEA algorithm. Then, we used machine learning methods to screen out OS gene set A related to the occurrence and prognosis of AML and OS gene set B related to treatment in leukemia stem cells (LSCs) like population (HSC-like). Furthermore, we screened out the hub genes in the above two gene sets and used them to identify molecular subclasses and construct a model for predicting therapy response. Results: Leukemia cells have different OS functions compared to normal cells and significant OS functional changes before and after chemotherapy. Two different clusters in gene set A were identified, which showed different biological properties and clinical relevance. The sensitive model for predicting therapy response based on gene set B demonstrated predictive accuracy by ROC and internal validation. Conclusion: We combined scRNAseq and bulk RNAseq data to construct two different transcriptomic profiles to reveal the different roles of OS-related genes involved in AML oncogenesis and chemotherapy resistance, which might provide important insights into the mechanism of OS-related genes in the pathogenesis and drug resistance of AML.


Assuntos
Leucemia Mieloide Aguda , Análise da Expressão Gênica de Célula Única , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Transcriptoma , Transformação Celular Neoplásica
8.
Inorg Chem ; 61(36): 14288-14296, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36040364

RESUMO

While research on lanthanide (Ln) complexes with silyl ligands is receiving growing attention, significantly unbalanced efforts have been devoted to different Ln elements. In comparison with the intense investigations on Ln elements such as Sm and Yb, the chemistry of silyl lanthanum and cerium complexes is much slower to develop, and no solid-state structure of a silyl lanthanum complex has been reported so far. In this research, four types of ate complexes, including [(DME)3Li][Cp3LnSi(H)Mes2], [(18-crown-6)K][Cp3LnSi(CH3)Ph2], [(DME)3Li][Cp3LnSiPh3], and [(12-crown-4)2Na] [Cp3LnSi(Ph)2Si(H)Ph2] (Ln = La, Ce), were synthesized by reacting [(DME)3Na][Cp3La(µ-Cl)LaCp3] or Cp3Ce(THF) with alkali metal silanides. All of the synthesized silyl Ln ate complexes were structurally characterized. La-Si bond lengths are in a range of 3.1733(4)-3.1897(10) Å, and the calculated formal shortness ratios of the La-Si bonds (1.071.08) are comparable to those in the reported silyl complexes having other Ln metal centers. The Ce-Si bond lengths (3.1415(6)-3.1705(9) Å) are within the typical range of reported silyl cerium ate complexes. 29Si solid-state NMR measurements on the diamagnetic silyl lanthanum complexes were conducted, and large one-bond hyperfine splitting constants arising from = 7/2) were resolved. Computational studies on these silyl lanthanum and cerium complexes suggested the polarized covalent feature of the Ln-Si bonds, which is in line with the measured large 1J139La-Si splitting constants.

9.
World J Clin Cases ; 10(13): 4214-4219, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35665134

RESUMO

BACKGROUND: Myocardial calcification is a rare complication in critically ill patients. The prognosis of myocardial calcifications in critically ill patients is very poor if not treated in a timely manner. We describe a rare case of acute extensive myocardial calcifications due to acute myocarditis after receiving extracorporeal membrane oxygenation (ECMO) support. CASE SUMMARY: We report a 17-year-old male patient who developed extensive myocardial calcifications while receiving prolonged ECMO support for severe myocarditis and cardiogenic shock. Extensive myocardial calcifications were confirmed by chest computed tomography (CT). Myocardial calcifications were observed in the left ventricle walls on CT examination 10 days after admission. The patient was then discharged with heart function class II on the NYHA classification. Two years later, the patient was still alive with adequate quality of life. We then included this patient and 7 other cases retrieved from the PubMed, Cochrane Library, EMBASE, and MEDLINE databases in our study, in order to provide a reference for the clinical diagnosis and treatment of this disease. CONCLUSION: Multiple causes including prolonged hemodynamic failure, profound acidosis, high vasopressor doses, and acute renal failure may jointly lead to extensive myocardial calcifications. The precise role of ECMO support in the timing and frequency of acute myocardial calcifications deserves further investigation.

10.
Front Psychiatry ; 13: 770714, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432013

RESUMO

Purpose: The purpose of this study is to explore the association of P300 components with clinical characteristics and efficacy of pharmacotherapy in alcohol use disorder (AUD). Methods: One hundred fifty-one AUD patients and 96 healthy controls were recruited and evaluated for the symptoms of depression, anxiety, sleep, and cognitive function by the Alcohol Use Disorders Identification Test (AUDIT), the 9-item Patient Health Questionnaire (PHQ-9), the 7-item Generalized Anxiety Disorder scale (GAD-7), the Pittsburgh Sleep Quality Index (PSQI), Digit Symbol Substitution test (DSST), and event-related potential P300, which is one of the averaged scalp electroencephalography responses time-locked to specific events. Among the AUD group, 101 patients finished an 8-week pharmacotherapy and were evaluated for the above data at post-intervention. Results: 1. At baseline, AUD patients had higher scores of AUDIT, PHQ-9, GAD-7, PSQI, and P300 latency at Cz, Pz, and Fz and lower DSST score and smaller P300 amplitudes at Fz, Cz, and Pz compared with controls. P300 components correlated significantly with alcohol dose and score of AUDIT, PHQ-9, GAD-7, PSQI, and DSST. 2. After 8 weeks' treatment, there were significant changes for the P300 components; alcohol dose; and score of AUDIT, PHQ-9, GAD-7, PSQI, and DSST. Variables at baseline, including P300 amplitudes at Fz, Cz, and Pz; latency of Fz and Pz; alcohol dose; and scores of PHQ-9, GAD-7, PSQI, and DSST, were significantly associated with changes of reduction rate of AUDIT scores. However, P300 amplitudes at Fz, Cz, and Pz in AUD patients after 8-week treatment were still significantly shorter than healthy controls (HCs), and P300 latencies at Fz, Cz, and Pz were significantly longer than HCs. 3. When validated area under the receiver operating characteristic curve (AUC) was over 0.80, the baseline variables including amplitudes at Cz and Pz, alcohol dose, and scores of PSQI could predict the changes of reduction rate of AUDIT score. Conclusion: P300 amplitudes and latencies at Fz, Cz, and Pz could be used as biological markers for evaluating the clinical characters and severity of AUD. P300 amplitudes at Cz and Pz, sleep condition, and cognitive function at baseline could predict the efficacy of pharmacotherapy for AUD patients.

11.
PLoS One ; 16(12): e0261239, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34932581

RESUMO

OBJECTIVE: To assess the cardiovascular safety of celecoxib compared to non-selective non-steroid anti-inflammatory drugs or placebo. METHODS: We included randomized controlled trials of oral celecoxib compared with a non-selective NSAID or placebo in rheumatoid arthritis and osteoarthritis patients. We conducted searches in EMBASE, Cochrane CENTRAL, MEDLINE, China National Knowledge Infrastructure, VIP, Wanfang, and Chinese Biomedical Literature Database. Study selection and data extraction were done by two authors independently. The risk of bias was assessed using Cochrane's risk-of-bias Tool for Randomized Trials. The effect size was presented as a risk ratio with their 95% confidence interval. RESULTS: Until July 22nd, 2021, our search identified 6279 records from which, after exclusions, 21 trials were included in the meta-analysis. The overall pooled risk ratio for Antiplatelet Trialists Collaboration cardiovascular events for celecoxib compared with any non-selective non-steroid anti-inflammatory drugs was 0.89 (95% confidence interval: 0.80-1.00). The pooled risk ratio for all-cause mortality for celecoxib compared with non-selective non-steroid anti-inflammatory drugs was 0.81 (95% confidence interval: 0.66-0.98). The cardiovascular mortality rate of celecoxib was lower than non-selective non-steroid anti-inflammatory drugs (risk ratio: 0.75, 95% confidence interval: 0.57-0.99). There was no significant difference between celecoxib and non-selective non-steroid anti-inflammatory drugs or placebo in the risk of other cardiovascular events. CONCLUSION: Celecoxib is relatively safe in rheumatoid arthritis and osteoarthritis patients, independent of dose or duration. But it remains uncertain whether this would remain the same in patients treated with aspirin and patients with established cardiovascular diseases.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Sistema Cardiovascular/efeitos dos fármacos , Celecoxib/uso terapêutico , Osteoartrite/tratamento farmacológico , Segurança do Paciente/normas , Artrite Reumatoide/patologia , Humanos , Osteoartrite/patologia
12.
ACS Appl Mater Interfaces ; 13(33): 39379-39393, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34374282

RESUMO

The research on supercapacitors (SCs) is one of the hot topics in the field of energy storage, and the intrinsic ageing mechanism of SCs is significant from both the economic and the scientific point of view. In this paper, the negative effects of decay of the key structural components on ageing of SCs were investigated by factorial design and analysis of variance (ANOVA). The ANOVA results showed that the degree of the negative influence on ageing of SCs could be ranked in descending order as anode > separator > cathode. The ageing would be accelerated due to the interaction between the electrode and separator, especially at a high charge-discharge current density. Further, the intrinsic chemical ageing mechanism of SCs was revealed by the morphology, microstructure, and chemical composition analyses of the fresh and aged key components (the electrode carbon materials, current collectors, and separators) with scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectra (XPS), time-of-flight secondary ion mass spectrometry (TOF-SIMS), wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR), etc. Moreover, the minimum pore width of electrode carbon materials suitable for electrolyte ion diffusion was obtained by density functional theory (DFT) calculations, which corroborated the assumption that the pore structure deterioration was one of the direct causes of capacitance loss for aged SCs. Generally, the ageing mechanism of key components of SCs could be a reference to develop advanced electrode materials and separators for SCs.

13.
Inorg Chem ; 60(13): 9688-9699, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34125520

RESUMO

Metalation of ß-diketiminato rare-earth metal complexes LnacnacLn(PhNCH2PPh2)2 (Ln = Y, Yb, Lu) with (COD)Pd(CH2SiMe3)2 afforded three-coordinate Pd(0) complexes supported by two sterically less bulky phosphines and a Pd → Ln dative interaction. The Pd(0) center is prone to ligation with isonitrile and CO; in the latter case, the insertion of a second CO with the Y-N bond was assisted via a precoordination of CO on the Pd(0) center, which led to the formation of an anionic Pd(0) carbamoyl. The reaction of the Pd-Y complex with iodobenzene showed a remarkable double P-C bond cleavage-formation pathway within the heterobimetallic Pd-Y core to afford (Ph3P)2PdI(Ph), imine PhNCH2, and a ß-diketiminato yttrium diiodide. In the related reaction of LnacnacY(PhNCH2PPh2)2 with (Ph3P)2PdI(Ph), the P-C bond cleavage following with a N-C bond formation was observed. Computational studies revealed a synergetic bimetallic mechanism for these reactions.

14.
ACS Omega ; 6(21): 13588-13600, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34095653

RESUMO

Gas chromatography-mass spectrometry (GC-MS) analysis has revealed extremely high abundances of rearranged hopanes in Jurassic source rocks and related crude oils in the center of the Sichuan Basin. The detected rearranged hopanes include 17α(H)-diahopanes (C27D and C29-35D), early-eluting rearranged hopanes (C27E and C29-33E), and 18α(H)-neohopanes (C29Ts and Ts). Both the 17α(H)-diahopanes and the early-eluting rearranged hopanes exhibit a distribution pattern similar to that of the 17α(H)-hopane series, with a predominance of the C30 member and the presence of 22S and 22R epimers of hopanes in the extended series (>C30). The results of this study show that the relatively high abundance of rearranged hopanes in Jurassic source rocks in the study area is associated with their depositional environments and with clay-mediated acidic catalysis rather than, as was previously thought, thermal maturity. Shallow lacustrine facies with brackish water and a suboxic to weak reducing sedimentary environment have contributed to the enrichment of rearranged hopanes, and clay-mediated acidic catalysis may also have had a positive influence on their abundance. The distribution patterns of the diahopane series indicate that the oils from Jurassic reservoirs in the Gongshanmiao Oilfield are sourced from Jurassic source rocks. Rearranged hopanes are therefore considered to be effective biomarkers for oil-source correlation in the center of the Sichuan Basin.

15.
Schizophr Res ; 231: 67-69, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33770628

RESUMO

OBJECTIVE: To explore pharmacogenetic relationships of NRG1 genotypes with neurocognitive performance and clinical symptoms after 12 week treatment of risperidone in Chinese Han first-episode schizophrenia. METHODS: A cohort of 221 patients with schizophrenia were recruited for this research. Finally 177 untreated first-episode patients were clinically evaluated with the Positive and Negative Syndrome Scale (PANSS), Raven's Standard Progressive Matrices (RSPM), Digit Vigilance Test (DVT), Digit Span (DS), underwent genotyping for five polymorphisms of NRG1, and completed a 12-week prospective study of risperidone monotherapy. RESULTS: 1. After risperidone treatment of 12 weeks, the total scores, positive score, negative score and general score of PANSS decreased significantly; the scores of RSPM, DVT and DS increased significantly. 2. No significant association with PANSS scores at baseline or change in scores after 12 weeks'treatment was found with any of the five SNPs. There was also neither significant association of DVT, DS or RSPM at baseline with any of the five SNPs. 3. After risperidone treatment of 12 weeks, rs3924999 and rs35753505 showed significant association with change in DVT and in RSPM in which there were significant differences among different genotype groups. CONCLUSION: This study suggested pharmacogenetic relationships between NRG1 variants and changes in cognition response with exposure to 12 weeks of treatment with risperidone. Two variants, rs3924999 and rs35753505, in the NRG1 gene were associated with the changes in attention and reasoning ability after risperidone treatment of 12 weeks.


Assuntos
Antipsicóticos , Neuregulina-1 , Risperidona , Esquizofrenia , Antipsicóticos/uso terapêutico , Povo Asiático , China , Humanos , Neuregulina-1/genética , Farmacogenética , Estudos Prospectivos , Risperidona/uso terapêutico , Esquizofrenia/tratamento farmacológico , Esquizofrenia/genética , Resultado do Tratamento
16.
Medicine (Baltimore) ; 99(3): e18806, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32011485

RESUMO

RATIONALE: Esophagopleural fistula (EPF) is a rare critical life-threatening condition that features high misdiagnosis rate. Although various surgical and conservative techniques have been developed for the treatment of EPF, the mortality rate of EPF remains high. PATIENT CONCERNS: An 81-year-old man with hepatic cirrhosis caused by schistosomiasis was admitted with upper gastrointestinal bleeding. DIAGNOSES: Upper endoscopy revealed bleeding large esophageal varices, and endoscopic injection sclerotherapy (EIS) was performed. Two weeks after the EIS was performed, the patient developed pyrexia, left-sided pleuritic chest pain. Air and pleural effusion were showed in the left pleural cavity by high-resolution computed tomography (HRCT), and a linear fistulous communication was noticed from the distal esophagus. These findings were consistent with hepatic cirrhosis, esophageal varices, upper gastrointestinal bleeding, and esophagopleural fistula. INTERVENTIONS: The patient was intensively treated with endoscopic self-expandable metallic stent (covered-SEMS) implantation and comprehensive treatments (including thoracic closed drainage, antibiotics, nasojejunal nutrition, and antacids). OUTCOMES: The patient was completely cured without recurrence during a 6 months of follow-up by comprehensive conservative treatments. LESSONS: This case indicates that pleural effusion with food residue is a specific finding in EPF. Thorax CT exhibited high sensitivity for the diagnosis of EPF. Endoscopic self-expandable metallic stent implantation and comprehensive conservative treatments may be preferable for the severe liver disease with EPF.


Assuntos
Endoscopia Gastrointestinal , Fístula Esofágica/etiologia , Varizes Esofágicas e Gástricas/terapia , Escleroterapia , Idoso de 80 Anos ou mais , Endoscopia Gastrointestinal/efeitos adversos , Endoscopia Gastrointestinal/métodos , Fístula Esofágica/diagnóstico por imagem , Fístula Esofágica/terapia , Varizes Esofágicas e Gástricas/diagnóstico por imagem , Varizes Esofágicas e Gástricas/etiologia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/terapia , Masculino , Esquistossomose mansoni/complicações , Esquistossomose mansoni/terapia , Escleroterapia/efeitos adversos , Escleroterapia/métodos , Stents Metálicos Autoexpansíveis
17.
Nat Commun ; 10(1): 5558, 2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31804470

RESUMO

The global urbanization rate is accelerating; however, data limitations have far prevented robust estimations of either global urban expansion or its effects on terrestrial net primary productivity (NPP). Here, using a high resolution dataset of global land use/cover (GlobeLand30), we show that global urban areas expanded by an average of 5694 km2 per year between 2000 and 2010. The rapid urban expansion in the past decade has in turn reduced global terrestrial NPP, with a net loss of 22.4 Tg Carbon per year (Tg C year-1). Although small compared to total terrestrial NPP and fossil fuel carbon emissions worldwide, the urbanization-induced decrease in NPP offset 30% of the climate-driven increase (73.6 Tg C year-1) over the same period. Our findings highlight the urgent need for global strategies to address urban expansion, enhance natural carbon sinks, and increase agricultural productivity.

18.
Medicine (Baltimore) ; 97(49): e13582, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30544481

RESUMO

RATIONALE: The Epstein-Barr (EB) virus has rarely been reported as a cause of fulminant myocarditis. To our knowledge, the present case is the first report on myocardial calcification in EB viral myocarditis and rhabdomyolysis. PATIENT CONCERNS: A 17-year-old man was admitted to the department with fever, chest tightness, and tachypnea that had been present for 2 days. DIAGNOSES: The initial investigation showed elevated liver enzyme levels, creatine kinase levels, creatine kinase isoenzyme levels, and elevated serum myoglobin. Echocardiography showed that left ventricular motion amplitude decreased. Test for immunoglobin M and immunoglobin G antibodies against Epstein-Barr virus were positive. These findings were consistent with fulminant myocarditis, cardiogenic shock, and rhabdomyolysis. INTERVENTIONS: The patient was intensively treated with venoarterial extracorporeal membrane oxygenation (VA-ECMO), continuous renal replacement therapy (CRRT). OUTCOMES: Myocardial calcification was observed in the left ventricle walls on CT examination 10 days after the admission. Four months later, the patient is still alive and with adequate daily life. LESSONS: This case indicates that this rare form of myocardial calcification may be associated with EB viral infection and rhabdomyolysis.


Assuntos
Calcinose/complicações , Infecções por Vírus Epstein-Barr/complicações , Miocardite/complicações , Rabdomiólise/complicações , Choque Cardiogênico/complicações , Adolescente , Calcinose/diagnóstico , Calcinose/terapia , Diagnóstico Diferencial , Infecções por Vírus Epstein-Barr/diagnóstico , Infecções por Vírus Epstein-Barr/terapia , Coração/diagnóstico por imagem , Humanos , Masculino , Miocardite/diagnóstico , Miocardite/terapia , Rabdomiólise/diagnóstico , Rabdomiólise/terapia , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/terapia
19.
Cancer Cell Int ; 18: 201, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30534002

RESUMO

BACKGROUND: There is increasing evidence that inflammation-based biomarkers are associated with tumor microenvironment which plays important roles in cancer progression. A high lymphocyte-to-monocyte ratio (LMR), has been suggested to indicate favorable prognoses in various epithelial cancers. We performed a meta-analysis to quantify the prognostic value of LMR in advanced-stage epithelial cancers undergoing various treatment. METHODS: We searched PubMed, EMBASE, Web of science and Cochrane Library up to July 2018 for relevant studies. We included studies assessing the prognostic impact of pretreatment LMR on clinical outcomes in patients with advanced-stage epithelial cancers. The primary outcome was overall survival (OS) and the secondary outcome was progression free survival (PFS). The summary hazard ratio (HR) and 95% confidence interval (CI) were calculated. RESULTS: A total of 8984 patients from 35 studies were included. A high pretreatment LMR was associated with favorable OS (HR = 0.578, 95% CI 0.522-0.641, P < 0.001) and PFS (HR = 0.598, 95% CI 0.465-0.768, P < 0.001). The effect of LMR on OS was observed among various tumor types. A higher pretreatment LMR was associated with improved OS in chemotherapy (n = 10, HR = 0.592, 95% CI 0.518-0.676, P < 0.001), surgery (n = 10, HR = 0.683, 95% CI 0.579-0.807, P < 0.001) and combined therapy (n = 11, HR = 0.507, 95% CI 0.442-0.582, P < 0.001) in the subgroup analysis by different therapeutic strategies. The cut-off value for LMR was 3.0 (range = 2.35-5.46). Subgroup analysis according to the cut-off value showed a significant prognostic value of LMR on OS and PFS in both subgroups. CONCLUSIONS: A high pretreatment LMR is associated with favorable clinical outcomes in advanced-stage epithelial cancers undergoing different therapeutic strategies. LMR could be used to improve clinical decision-making regarding treatment in advanced epithelial cancers.

20.
Phys Chem Chem Phys ; 19(34): 23204-23212, 2017 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-28825439

RESUMO

Design of a solid solution with tunable functionality is an attractive strategy toward realizing novel devices with multi-functionalities. In this work, a series of Ca1-xCdxWO4 solid solutions in the entire range 0 ≤ x ≤ 1 with tetragonal scheelite structure have been successfully prepared for the first time. X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and Fourier transform Raman (FT-Raman) spectroscopies indicated that all the nanocrystals have a tetragonal scheelite structure without wolframite phase. Structural refinement data revealed that the lattice volume decreased with the replacement of Ca2+ by Cd2+ ions. UV-Vis diffuse reflectance spectra indicated that optical band gap reduced with the replacement of Ca2+ by Cd2+ ions. Scanning electron microscopic (SEM) images showed that morphologies of the nanocrystals changed with the chemical compositions. The structure evolution of the solid solutions was further investigated by high-resolution transmission electron microscopy (HRTEM). Moreover, the influence of chemical compositions on the photoluminescent and electric performance has been performed and discussed. The reported synthetic approach and findings reported here are important to understand the structure and structure-property relation of scheelite-structured tungstate and molybdate compounds, which has potential applications in the design of other kinds of novel functional materials.

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