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1.
Zhonghua Xin Xue Guan Bing Za Zhi ; 52(1): 72-78, 2024 Jan 24.
Artigo em Zh | MEDLINE | ID: mdl-38220458

RESUMO

Objective: To investigate the effects of exosome derived from miR-133a-3p engineered human umbilical cord blood mesenchymal stem cells (ucMSC) on myocardial repair after acute myocardial infarction (AMI) in rats. Methods: UcMSC was amplified and cultured in vitro. Lentiviral carrying miR-133a-3p and negative control vectors were transfected into ucMSC. Exosomes secreted by the transfected ucMSC were named miR-133a-3p-Exo and miR-NC-Exo, respectively. The AMI model of rats was established by ligation of the left anterior descending coronary artery. MiR-133a-3p-Exo or miR-NC-Exo were then injected into the border zone of the infarct area. Cardiac function was assessed by echocardiography after twenty-eight days of intervention, and Masson staining was used to evaluate the area of myocardial fibrosis post-AMI. The myocardial apoptosis after infarction was evaluated by TUNEL staining and the angiogenesis after infarction was evaluated by immunofluorescence staining in the current study. Results: Compared with the miR-NC-Exo group, the left ventricular ejection fraction in the miR-133a-3p-Exo group was significantly increased ((47.4%±9.8%) vs. (64.2%±8.9%), P<0.05). While the myocardial fibrosis area ((31.2%±7.3%) vs. (18.0%±1.5%), P<0.01) and the percentage of apoptotic cardiomyocytes ((25.6%±3.6%) vs. (15.1%±4.4%), P<0.05) was significantly reduced in the miR-133a-Exo group. Besides, the expression of CD31 and α-smooth muscle actin (α-SMA) were also increased significantly in the miR-133a-3p-Exo group compared to the miR-NC-Exo group (CD31: (2.9±0.9) vs. (13.9±2.0), P<0.000 1, α-SMA: (3.5±0.9) vs. (11.0±1.6), P<0.000 1). Conclusion: Exosome derived from miR-133a-3p engineered ucMSC effectively inhibited myocardial apoptosis and promoted angiogenesis, thus improving the cardiac function after myocardial infarction in rats.


Assuntos
Cardiomiopatias , Exossomos , Células-Tronco Mesenquimais , MicroRNAs , Infarto do Miocárdio , Ratos , Humanos , Animais , Exossomos/metabolismo , Volume Sistólico , Ratos Sprague-Dawley , MicroRNAs/genética , Função Ventricular Esquerda , Infarto do Miocárdio/genética , Cardiomiopatias/metabolismo , Fibrose , Células-Tronco Mesenquimais/metabolismo , Apoptose
2.
Zhonghua Wai Ke Za Zhi ; 61(12): 1065-1073, 2023 Dec 01.
Artigo em Zh | MEDLINE | ID: mdl-37932142

RESUMO

Objective: To compare the efficacy of lower extremity three dimensional CT venography (CTV) and lower extremity ascending phlebography in evaluating recurrent varicose veins. Methods: A retrospective analysis was conducted on clinical data from 235 patients with unilateral recurrent varicose veins who were treated at the Department of Vascular Surgery,Beijing Shijitan Hospital,Capital Medical University, between January 2015 and December 2020.There were 112 males and 123 females, with an age of (62.5±11.4)years (range:24 to 75 years).Patients were stratified into two groups based on preoperative imaging examination:the CTV group (utilizing lower extremity venous ultrasound+lower extremity CTV) and the control group (employing lower extremity venous ultrasound+lower extremity ascending phlebography).The two groups were matched in a 1∶1 ratio using propensity score matching, resulting in 43 cases per group.Comparative analyses between the groups at the one-year postoperative follow-up were performed using independent sample t tests, Wilcoxon rank-sum tests, χ2 tests, and linear regression analysis. Results: One year post-surgery,the CTV group exhibited a lower venous clinical severity score (VCSS) compared to the control group(M(IQR),3.0(4.3) vs.4.0(5.8),Z=-2.038,P=0.040).Additionally, the chronic venous insufficiency patients' quality of life questionnaire (CIVIQ-20) scores were significantly higher in the CTV group than in the control group (89.0(8.0) vs.82.5(17.0), Z=-2.627, P=0.010).Patients in the CTV group also experienced a shorter ulcer healing time compared to the control group (4.0(4.0) weeks vs.12.0(7.0) weeks, Z=-3.217,P<0.01).Both groups showed no clinically symptomatic recurrent varicose veins or ulcers.However, they exhibited ultrasound-detectable varicose vein recurrence, with no statistically significant difference (χ2=0.453,P=0.500).The number of diseased vessels requiring management based on ultrasound supplemented by CTV was 16, while the number supplemented by ascending phlebography was 7,with a statistically significant difference (χ2=4.800,P=0.030).Linear regression analysis demonstrated that clinical-etiology-anatomy-pathology clinical grading and the preoperative imaging examination method exerted independent influences on VCSS and CIVIQ-20 during the one-year postoperative assessment. Conclusions: CTV-assisted ultrasound enables a direct and comprehensive evaluation and localization of diseased veins in patients with recurrent varicose veins.The utilization of lower extremity vein ultrasound combined with CTV-guided management of lower extremity vessels in minimally invasive treatment significantly improves patient prognosis, surpassing the assessment provided by ascending phlebography.


Assuntos
Varizes , Insuficiência Venosa , Masculino , Feminino , Humanos , Flebografia/métodos , Estudos Retrospectivos , Pontuação de Propensão , Qualidade de Vida , Varizes/diagnóstico por imagem , Varizes/cirurgia , Tomografia Computadorizada por Raios X/métodos , Insuficiência Venosa/diagnóstico
3.
Zhonghua Nei Ke Za Zhi ; 61(8): 883-892, 2022 Aug 01.
Artigo em Zh | MEDLINE | ID: mdl-35922212

RESUMO

Psoriatic arthritis is a chronic systemic autoimmune disease, characterized by psoriasis skin lesions and inflammation of the spine and joint. It has complicated clinical manifestations and individual variations. Nearly half of the patients will have joints erosion in two years, which is crippling. The severity of the skin and joint disease frequently do not correlate with each other. Currently, the understanding of the disease is insufficient in China with the lack of standardized diagnosis and treatment. Therefore, researchers from the Chinese Rheumatology Association formulated this specification based on the diagnosis and management experience together with guidelines at home and abroad. The specification summarizes the present situation of domestic diagnosis and treatment, aiming to standardize the diagnosis process and treatment protocols of psoriatic arthritis. Furthermore, it can reduce misdiagnosis and missed diagnosis, as well as improve the prognosis.


Assuntos
Artrite Psoriásica , Psoríase , Reumatologia , Artrite Psoriásica/diagnóstico , Artrite Psoriásica/terapia , China , Humanos , Prognóstico , Psoríase/diagnóstico , Pele
4.
Zhonghua Yi Xue Za Zhi ; 101(42): 3495-3500, 2021 Nov 16.
Artigo em Zh | MEDLINE | ID: mdl-34775708

RESUMO

Objective: To explore risk factors for hyperkalemia in hemodialysis (HD) patients, and establish and verify a risk assessment model of hyperkalemia in HD patients. Methods: The clinical data of HD patients who were admitted to the Department of Nephrology of the First Affiliated Hospital of Zhengzhou University between April 2020 and January 2021 were retrospectively collected and divided into training dataset and validation dataset by using the conversion-random number generator. In the training dataset, multivariate logistic regression analysis was used to screen the risk factors for hyperkalemia in HD patients and the factors were scored to establish the risk assessment model. The validation dataset was substituted into the model and the receiver operating characteristic (ROC) curve was drawn and the area under the curve (AUC) was calculated to verify the effectiveness of the risk prediction model in predicting hyperkalemia. Results: A total of 502 HD patients were enrolled and further divided into training dataset (n=372) and validation dataset (n=130). There were 268 males and 234 females, with a mean age of (54±13) years. Multivariate logistic regression analysis showed that metabolic acidosis, high potassium diet, history of hyperkalemia, the change of electrocardiogram (ECG), disfunction of vascular access and time interval from last dialysis were risk factors for causing hyperkalemia in patients undergoing HD. Risk assessment model was established based on these risk factors. The AUC of the ROC curve was 0.799. Using 5 as the cut-off value, the sensitivity and specificity for predicting hyperkalemia events was 61.4% and 86.3%, respectively. Conclusion: The current study preliminarily established a risk assessment model for hyperkalemia in HD patients, which can help clinicians manage the potassium level of HD patients.


Assuntos
Hiperpotassemia , Adulto , Idoso , Feminino , Humanos , Hiperpotassemia/epidemiologia , Masculino , Pessoa de Meia-Idade , Curva ROC , Diálise Renal , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
5.
Zhonghua Wai Ke Za Zhi ; 59(5): 366-369, 2021 May 01.
Artigo em Zh | MEDLINE | ID: mdl-33915627

RESUMO

Objective: To examine the long-term efficacy of radiofrequency closure in the treatment of great saphenous vein varicose. Methods: The clinic data of 185 patients with varicose veins of lower limbs treated with radiofrequency closure admitted at Department of Vascular Surgery, Beijing Shijitan Hospital, Capital Medical University from July 2016 to January 2017 was analyzed retrospectively. A total of 203 limbs were treated by radiofrequency closure. The long-term efficacy of radiofrequency closure was evaluated by analyzing the closure rate, clinical-etiology- anatomy-pathophysiology (CEAP) grading, venous clinical severity score (VCSS), chronic venous insufficiency questionnaire (CIVIQ) score, and complications, using repeated measures analysis of variance. Results: All procedures were successful. The closure rate was 98.0% (199/203) at one year and two years postoperative, which was still maintained at 97.5% (198/203) at 3 years of follow-up. Postoperative CEAP grading was significantly downgraded compared with that before the operation. Totally 88.4% (76/86) of C5 to C6 grade patients downgraded to C2 to C4 grade at 6 months, and 95.3% (82/86) downgraded to C0 to C2 garde at 3 years postoperative. VCSS and CIVIQ score in both groups significantly improved at all follow-up time points compared to preoperative scores (VCSS: F=1 064.7, P=0.003; CIVIQ score: F=2 984.3, P=0.001). The most common complication was subcutaneous blood stasis (10.8%), most of which disappeared within 1 month after the surgery. Other complications included pigmentation and thrombophlebitis (5.9% and 3.9%, respectively). Conclusion: The long-term efficacy of radiofrequency closure of the great saphenous vein is satisfactory.


Assuntos
Varizes , Insuficiência Venosa , Humanos , Estudos Retrospectivos , Veia Safena/cirurgia , Índice de Gravidade de Doença , Resultado do Tratamento , Varizes/cirurgia , Insuficiência Venosa/cirurgia
6.
Fa Yi Xue Za Zhi ; 35(3): 295-299, 2019 Jun.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-31282623

RESUMO

ABSTRACT: Objective To explore polygraph accuracy of Control Question Test (CQT)and whether it could be influenced by examinee's education level and type of violation of law. Methods Real cases of CQT (n=104) and the data from MAO (n=296) were collected. The polygraph accuracy of CQT was calculated. Variance analysis on three groups of different education levels was used to compare their age, and then the chi-square test was employed to compare polygraph accuracy among the groups. Independent sample t test was used to compare the age of subjects in the two groups of different types of violation of law, and then chi-square test was used to compare the true positive rate and true negative rate of lie detection after integration. Results In CQT lie detection of criminal cases, the true positive rate was 87.00%, the false negative rate was 13.00%, the true negative rate was 82.20%, and the false positive rate was 17.80%. There was no statistical significance in the differences between the true positive rate and the true negative rate (P>0.05). In CQT lie detection of the groups of different education levels, there was no statistical significance in the differences between the true positive rates (P>0.05) while the differences between the true negative rates had statistical significance (P<0.05). There was no statistical significance in the differences of both the true positive rates and the true negative rates between the violent violation of law and non-violent violation of law (P>0.05). Conclusion There is no significant difference between the efficiency of CQT lie detection of identifying criminals and excluding innocents. However, a comparatively high false positive rate and false negative rate still exist. The efficiency of CQT lie detection identifying criminals may not influenced by the examinee's education level and type of violation of law, but its efficiency of excluding innocents may be influenced by the examinee's education level.


Assuntos
Criminosos , Detecção de Mentiras , Monitorização Fisiológica , Psicofisiologia
7.
Phys Rev Lett ; 118(20): 205501, 2017 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-28581808

RESUMO

Multielement solid solution alloys are intrinsically disordered on the atomic scale, and many of their advanced properties originate from the local structural characteristics. The local structure of a NiCoCr solid solution alloy is measured with x-ray or neutron total scattering and extended x-ray absorption fine structure (EXAFS) techniques. The atomic pair distribution function analysis does not exhibit an observable structural distortion. However, an EXAFS analysis suggests that the Cr atoms are favorably bonded with Ni and Co in the solid solution alloys. This short-range order (SRO) may make an important contribution to the low values of the electrical and thermal conductivities of the Cr-alloyed solid solutions. In addition, an EXAFS analysis of Ni ion irradiated samples reveals that the degree of SRO in NiCoCr alloys is enhanced after irradiation.

8.
Zhonghua Yi Xue Za Zhi ; 97(24): 1875-1877, 2017 Jun 27.
Artigo em Zh | MEDLINE | ID: mdl-28648012

RESUMO

Objective: To assess the validity of Caprini risk assessment model in prediction of venous thromboembolism in Chinese hospitalized patients in a general hospital. Methods: Medical record review was performed in Beijing Shijitan Hosital for all eligible hospitalized patients who underwent screening for venous thromboembolism between January and December 2015. The Caprini score of patients with or without venous thromboemboilism and incidence of venous thromboembolism in patients with various Caprini risk levels, surgery and medical patients was compared. Results: A total of 6 966 inpatients were enrolled. Three hundred and ninety-six patients developed venous thromboembolism. The Caprini median score of patients with venous thromboemboilism was 5 (3-7), which higher than 3(2-5) of patients without venous thromboembolism(Z=-13.68, P<0.01). Incidence of venous thromboembolism of patients in low, moderate, high, highest risk level was 1.0%, 1.8%, 5.7%, 10.6%, respectively. There was no statistically significant difference of incidence between low and moderate risk patients (OR=1.88, 95%CI: 0.89-3.99, P>0.05), but significant difference between moderate and high risk (OR=3.23, 95%CI: 2.06-5.06, P<0.01), high and highest risk patients (OR=1.97, 95%CI: 1.59-2.45, P<0.01). There was no incidence difference of venous thromboembolism between surgery and medical patients in the same Caprini level of low (χ(2)=3.58 , P>0.05), moderate(χ(2)=2.89, P>0.05), high(χ(2)=0.46, P>0.05), highest risk(χ(2)=1.61, P>0.05). Conclusion: Caprini risk assessment model can effectively predict the occurence of venous thromboembolism in Chinese hospitalized patients with high risk of VTE(Caprini score >2)in a general hospital.


Assuntos
Medição de Risco , Tromboembolia Venosa/epidemiologia , Pequim , Hospitais Gerais , Humanos , Estudos Retrospectivos , Fatores de Risco
10.
Genet Mol Res ; 15(4)2016 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-27819724

RESUMO

Adipose-derived stem cells (ADSCs) show nearly unlimited potential in medical and animal science. Currently, understanding of the biological mechanisms regulating ADSC growth in vitro remains very limited. Histone acetylation, an epigenetic modification, plays a key role in maintaining stem cell properties. To further study its effect on ADSC growth characteristics in vitro, we treated goat ADSCs with the histone deacetylase inhibitors trichostatin A (TSA) and vorinostat (SAHA). This inhibited SIRT1 expression and increased histone H3K9 acetylation, leading to decreased cell viability, cell cycle arrest, and apoptosis. Quantitative real-time polymerase chain reaction revealed that H3K9 hyperacetylation stimulated transcription of NANOG, OCT4, SOX2, and TERT, but inhibited that of PCNA, P53, and BAX. Western blotting indicated that TSA and SAHA increased protein expression of NANOG, reduced that of SOX2, TERT, PCNA, P53, and BAX, and did not change that of OCT4. These findings provide new experimental evidence contributing to our understanding of the mechanisms underlying ADSC growth characteristics in vitro.


Assuntos
Tecido Adiposo/citologia , Histonas/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Acetilação , Animais , Apoptose/genética , Western Blotting , Ciclo Celular/genética , Proliferação de Células , Sobrevivência Celular/genética , Citometria de Fluxo , Regulação da Expressão Gênica , Cabras , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
11.
Mol Biol (Mosk) ; 50(3): 496-503, 2016.
Artigo em Russo | MEDLINE | ID: mdl-27414788

RESUMO

ZNF143 is a ubiquitously expressed transcription factor conserved in vertebrates and might regulate the expression of numerous genes. But its function in mediating chromatin interactions remains elusive. By integrated analysis of public datasets, we provided evidence that a majority of ZNF143 binding sites (BSs) were involved in CTCF-mediated chromatin interaction networks (CTCF-CINs) by overlapping with cohesin-BSs and CTCF-BSs. We further showed that only a very few CTCF-CINs were associated with ZNF143 alone, whereas those associated with ZNF143 and cohesin simultaneously were highly overlapped with constitutive, conserved CTCF-BSs and enriched at boundaries of chromatin topologically associating domains. These observations implicate that as an important partner of CTCF, ZNF143 helps it establish the conserved chromatin structure by cooperating with cohesin.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Cromatina/química , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Repressoras/metabolismo , Transativadores/metabolismo , Sítios de Ligação , Fator de Ligação a CCCTC , Proteínas de Ciclo Celular/genética , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina , Proteínas Cromossômicas não Histona/genética , Bases de Dados Genéticas , Expressão Gênica , Humanos , Células K562 , Motivos de Nucleotídeos , Ligação Proteica , Mapeamento de Interação de Proteínas , Proteínas Repressoras/genética , Transativadores/genética , Coesinas
12.
Eur Rev Med Pharmacol Sci ; 26(5): 1607-1617, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35302207

RESUMO

OBJECTIVE: Ciprofol is a newly developed intravenous sedative-hypnotic drug. The objective of the study was to prove whether ciprofol was non-inferior to propofol for the successful induction of general anesthesia. The ideal post-induction sedation level was assessed by comparing patients' clinical symptoms and their hemodynamic effects in responding to noxious stimuli, mostly tracheal intubation and bispectral index (BIS) alterations following ciprofol/propofol administration. PATIENTS AND METHODS: In this multi-center, randomized, double-blind phase 3 trial, selective surgery patients were randomly assigned in a 1:1 ratio to either ciprofol 0.4 mg/kg (n = 88) or propofol 2.0 mg/kg (n = 88) groups. The primary endpoint was the percentage of patients with successful anesthesia inductions. Secondary endpoints included the times to successful induction of general anesthesia and loss of the eyelash reflex, changes in BIS, as well as safety indicators. RESULTS: The anesthesia induction success rates for both ciprofol 0.4 mg/kg and propofol 2 mg/kg groups were 100.0%, with a 95% CI lower success limit of -4.18% difference between the two groups, indicating that ciprofol was non-inferior to propofol. For secondary outcomes, the average time to successful anesthesia and loss of the eyelash reflex were 0.91 min and 0.80 min for ciprofol and 0.80 min and 0.71 min for propofol, respectively. The pattern of BIS changes with ciprofol was similar to propofol and stable during the anesthesia maintenance period. Safety was comparable with 88.6% TEAEs in the ciprofol group compared to 95.5% in the propofol group. The incidence of injection pain was significantly lower in the ciprofol group compared to the propofol group (6.8% vs. 20.5%, p < 0.05). In addition, the patients treated with ciprofol had a lesser increase in blood pressure and heart rate, and fewer cases with BIS > 60 within 15 min of intravenous administration, which indicated that ciprofol may provide a better ideal sedation level during the post-induction period under an equivalent dosing regimen to propofol. CONCLUSIONS: Ciprofol for patients undergoing selective surgery is a new option for the induction of general anesthesia.


Assuntos
Propofol , Anestesia Geral , Anestésicos Intravenosos , Método Duplo-Cego , Procedimentos Cirúrgicos Eletivos , Humanos , Hipnóticos e Sedativos , Propofol/farmacologia
13.
Insect Mol Biol ; 20(4): 519-27, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21585579

RESUMO

Thymosins have diverse biological activities including actin-sequestering and tissue repair in vertebrates, however, there is little information about the function of thymosins in invertebrates. We isolated a ß-thymosin gene in Helicoverpa armigera. It has two transcript variants, HaTHY1 and HaTHY2, encoding 19.0 kDa and 14.5 kDa peptides, respectively. HaTHY1 was mainly transcribed in the integument and midgut, while HaTHY2 was principally presented in the fat body and haemocytes. The transcript levels of HaTHY2 showed some fluctuation; there was an obvious increase at the metamorphic stage in the integument or fat body. HaTHY was able to be upregulated by 20-hydroxyecdysone or by bacterial and viral challenge. These data suggest that HaTHY is upregulated by the steroid hormone and by responses to microorganism infection.


Assuntos
Ecdisterona/metabolismo , Mariposas/metabolismo , Timosina/metabolismo , Processamento Alternativo , Sequência de Aminoácidos , Animais , Sequência de Bases , Escherichia coli , Expressão Gênica , Klebsiella pneumoniae , Dados de Sequência Molecular , Mariposas/crescimento & desenvolvimento , Mariposas/imunologia , Mariposas/microbiologia , Nucleopoliedrovírus , Isoformas de Proteínas , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Regulação para Cima
14.
J Phys Condens Matter ; 33(18)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33711824

RESUMO

LiTaO3crystals irradiated with 3 MeV and 1.162 GeV Au ions were studied by single crystal x-ray diffraction and Raman scattering measurements. The maximum lattice strains after 3 MeV Au ion irradiation to a fluence of 1.2 × 1013 cm-2were 1.2% and 0.6% along thec- anda-/b-axes, respectively. Two effects were observed in 1.162 GeV Au ion irradiated samples: (i) the (0006) and (1120) Bragg peaks were split into doublets, which suggested a subtle structural change due to slight modification of chemical composition; and (ii) the pre-damaged 1.2% lattice strain along thec-axis was relaxed to 0.9% after subsequent irradiation with 1.162 GeV Au ions, while relaxation along thea- orb-axis was not obvious. A distinct change in the Raman spectrum of the 〈0001〉 oriented LiTaO3crystals was observed after 1.162 GeV Au ion irradiation, but no obvious change was observed in the 〈1120〉 oriented samples or in 3 MeV Au ion irradiated samples. Strain and structural changes in crystalline LiTaO3, with or without pre-existing defects, upon ion irradiation are delineated in its responding to inelastic ionization and elastic nuclear collisions.

15.
Phys Rev Lett ; 105(1): 015503, 2010 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-20867461

RESUMO

Pressure-induced cation and anion disordering in La2Zr2O7 pyrochlore is quantitatively analyzed by Rietveld refinement of in situ x-ray diffraction patterns, Raman, and infrared measurements. An anomalous lattice expansion and obvious change of the pressure dependence of the vibrational modes occur at ∼10 GPa. The pressure-induced water incorporation in the La2Zr2O7 pyrochlore structure may be related to a previously noted photoelectrochemical effect.

16.
Phys Chem Chem Phys ; 12(39): 12472-7, 2010 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-20721363

RESUMO

Ab initio total-energy calculations and X-ray diffraction measurements have been combined to study the phase stability of zirconate pyrochlores (A(2)Zr(2)O(7); A = La, Nd and Sm) under pressures up to 50 GPa. Phase transformations to the defect-cotunnite structure are theoretically predicted at pressures of 22, 20 and 18 GPa, in excellent agreement with the experimentally determined values of 21, 22 and 18 GPa for La(2)Zr(2)O(7), Nd(2)Zr(2)O(7) and Sm(2)Zr(2)O(7), respectively. Analysis of the elastic properties indicates that elastic anisotropy may be one of the driving forces for the pressure-induced cubic-to-noncubic phase transformation.

17.
Environ Pollut ; 258: 113716, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31831225

RESUMO

Organic carbon is an essential element for sustainable soil management. While the effects of microplastics on soil physical and biological properties are presenting, it remains unclear whether the organic carbon dynamics of soil are altered by increased microplastic accumulation. The objectives of this study were to evaluate the influences of different polyester microfiber (PMF 0, 0.1% and 0.3% of soil dry weight) and organic material (OM 0, 1%, 2% and 3% of soil dry weight) addition levels on soil organic carbon and to determine the PMF distribution in aggregates from a pot experiment. After 75 days of incubation under 6 wet-dry cycles, the concentrations of soil total organic carbon did not differ significantly between the PMF (9.7 ± 6.6 g kg-1) and control (9.7 ± 6.9 g kg-1) treatments. However, PMF addition significantly reduced the organic carbon concentration in the large (>2 mm) macro-aggregates compared to the control treatment (10.6 ± 4.8 g kg-1 vs. 11.7 ± 4.4 g kg-1), but the results were opposite in the small (2-0.25 mm)macro-aggregates (10.2 ± 4.9 g kg-1 vs. 8.4 ± 3.8 g kg-1). In this study, less than 30% of added PMFs were incorporated into soil aggregates. In addition, the abundance and average length of aggregate-associated PMF in the large (2210 ± 180 particles per g aggregate and 2.08 ± 0.17 mm) and small (1820 ± 150 particles per g aggregate and 1.68 ± 0.11 mm) macro-aggregates were significantly greater than those in the micro-aggregates (1010 ± 70 particles per g aggregate and 0.72 ± 0.05 mm). Our results demonstrate that the distribution of organic carbon in soil macro-aggregates is affected by PMFs addition. Thus, we propose that the behavior of microplastics inside soil aggregates should be further explored to clarify their effects on the physical protection of soil organic carbon.


Assuntos
Carbono/análise , Argila , Plásticos/análise , Poliésteres/análise , Solo/química
18.
Eur Rev Med Pharmacol Sci ; 24(12): 7101-7113, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32633405

RESUMO

OBJECTIVE: Postoperative cognitive dysfunction (POCD) is a common complication after general anesthesia in the elderly people. Dual-specificity phosphatase 14 (DUSP14, also known as MKP6) has been implicated in the pathogenesis of various inflammatory diseases. However, the exact role and mechanism of DUSP14 in POCD remains unclear. MATERIALS AND METHODS: An isoflurane exposure induced POCD aged rat model was successfully constructed. The pathological changes of hippocampal tissues of aged rats were detected by Nissl staining. Evaluation of learning and memory abilities in aged rats was measured using Morris water maze task test. The DUSP14 level was detected by immunohistochemistry (IHC) assay, quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot, respectively. Levels of brain injury markers [S-100ß and neuron specific enolase (NSE)] and inflammatory cytokines [interleukin (IL)-1ß (tumor necrosis factor (TNF)-α and IL-6] were detected using Enzyme Linked Immunosorbent Assay (ELISA) or qRT-PCR. The apoptosis of hippocampal nerve cells was assessed by Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. Western blot assay was used to measure the expression of proteins related to apoptosis, pyroptosis and NOD-like receptor family pyrin domain-containing 3 (NLRP3)-Caspase-1 pathway. RESULTS: Isoflurane exposure led to brain injury, inflammatory response, cognitive dysfunction in aged rats and decreased the expression of DUSP14. Overexpression of DUSP14 could inhibit apoptosis, inflammation, pyroptosis, brain tissue damage, and improve cognitive dysfunction of aged rats after isoflurane anesthesia. Further mechanism studies revealed that DUSP14 may play a neuroprotective effect on POCD by regulating NLRP3 inflammasome-mediated pyroptosis. CONCLUSIONS: DUSP14 may effectively protect against isoflurane-induced neuro-inflammation, brain damage and cognitive dysfunction, indicating that DUSP14 may be a potential predictor and therapeutic target for POCD.


Assuntos
Envelhecimento , Disfunção Cognitiva/tratamento farmacológico , Fosfatases de Especificidade Dupla/metabolismo , Inflamassomos/efeitos dos fármacos , Inflamação/tratamento farmacológico , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Fármacos Neuroprotetores/farmacologia , Animais , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Fosfatases de Especificidade Dupla/genética , Inflamassomos/metabolismo , Inflamação/metabolismo , Inflamação/patologia , Isoflurano/antagonistas & inibidores , Isoflurano/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fármacos Neuroprotetores/metabolismo , Piroptose/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
19.
J Phys Condens Matter ; 32(7): 074002, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-31675736

RESUMO

The local structure of Ni80X20 (X: Cr, Mn, Pd) solid-solution alloys was investigated with x-ray absorption and total scattering x-ray diffraction methods. Atomic pair distribution function (PDF) analysis indicated that the local lattice distortion is strongly relevant to the atomic size mismatch, and the local lattice distortion in Ni80Pd20 alloy is obviously larger than that in other solid-solution alloys. The bond length of different atomic pairs was derived from the fitting of extended x-ray absorption fine structure spectra. Quantitative analysis of the local bonding environment in Ni80Cr20 during Ni ion irradiation suggested that Cr atoms tend to form clusters in Ni80Cr20 with the increase of ion dose.

20.
J Phys Condens Matter ; 32(35): 355405, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32353841

RESUMO

Polar phonon modes associated with room temperature ferroelectricity are observed in SrTiO3 single crystals irradiated with Ti ions. Quantitative strain analysis reveals that irradiation-induced out-of-plane strain drives the centrosymmetric cubic SrTiO3 to a tetragonal-like structure in the maximum damaged region. Energy transfer from ions to electrons during ion irradiation yields defects in SrTiO3 that also plays an important role for the room temperature ferroelectricity. Different from thin film techniques, the ferroelectricity in the ion irradiated SrTiO3 can occur for much larger thicknesses, depending on the energy and type of ion.

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