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1.
J Colloid Interface Sci ; 558: 21-31, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31580952

RESUMO

Three-dimensional graphitic carbon materials with controllable composition and hierarchically porous structure are promising electrode materials for supercapacitors. In this work, a modified phase inversion method combined with a calcination process was developed to prepare three-dimensional graphene networks embedded with nitrogen-doped carbon nanoparticles. When used as electrode for supercapacitors, the as-prepared material delivered a high capacitance of 431.9 F g-1 at 0.1 A g-1 and 156.8 F g-1 at 20 A g-1, as well as a stable cyclic behavior with no capacitance decay after 5000 cycles. Such a remakable capacitive performance was attributed to its hierarchically porous structure and proper nitrogen doping content (9.68 ±â€¯0.24 at%), which facilitated the migration of electrolyte ions and provided abundant redox active sites for the faradic reactions. The synthetic strategy may be exploited for the rational design and synthesis of new carbon materials with controlled doping level and three-dimensional porous structure.

2.
J Colloid Interface Sci ; 558: 211-219, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31586740

RESUMO

Porous interconnected carbon nanosheets (PICNs) with high electrochemical performance were prepared by doping urea and a co-hydrothermal precursor derived from soybean stalk (SS) and nickel nitrate. The specific surface area and average pore diameter of the as-synthesized PICNs are 2226.29 m2 g-1 and 1.89 nm, and their N and O contents are 5.08% and 9.4%, respectively, which is beneficial for increasing pseudocapacitance. Furthermore, the doping of the metal Ni increases the graphitization degree of the PICNs and promotes the conversion of pyridine-N to graphitized-N. Therefore, the PICNs possess a high specific capacitance of 407 F g-1 at a current density of 0.5 A g-1, a high capacitance retention of 78.62% even at 20 A g-1, and an outstanding cycling stability (over 93% retention rate after 10,000 charge/discharge cycles). Moreover, an energy density of 36.11 W h kg-1 is achieved at a power density of 517.8 W kg-1 during a two-electrode system test, and a retention rate of 87.5% is obtained after 10,000 cycles. This co-hydrothermal treatment as well as nitrogen-doping approach for preparing porous interconnected carbon from SS not only represents an alternative strategy for carbon-based supercapacitor materials but also provides a new option for the utilization of waste SS.

3.
J Nanosci Nanotechnol ; 20(4): 2622-2627, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492286

RESUMO

Black TiO2-graphene oxide (GO) nanocomposites are synthesized via the pulsed laser ablating TiO2 powders and GO in deionized water. The simple process enables the preparation of black TiO2 nanoparticles and anchors them onto the GO sheet in one step. The TiO2-GO nanocomposites exhibit greatly enhancement for photocatalytic degradation of Rhodamine B (RB) dye in comparison with the pristine and the ablated black TiO2. The heterojunction structure plays an important role in efficient charge separation, which reduces the recombination of photogenerated electrons and holes. The unique two-dimensional structure of GO enables the composite to have a large specific surface area, and prevents the agglomeration of TiO2 nanoparticles, which are beneficial to the photocatalytic performance of the composite.

4.
Sci Total Environ ; 699: 134262, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31677473

RESUMO

Chemical oxidation is an effective method to improve the ability of biochars for metals removal, but there are too few studies on screening of high-efficiency oxidants and quantitative analysis of sorption mechanisms. In this study, rape straw biochars (BC) were oxidized with HNO3, H2O2, and KMnO4, and noted as BC-HNO3, BC-H2O2, and BC-Mn, respectively. The Pb removal capacities and quantitative sorption mechanisms of biochars were explored through batch sorption experiments. Compared with that of BC (175 mmol kg-1), the maximum Pb sorption capacities of BC-HNO3 and BC-H2O2 increased to 526 and 917 mmol kg-1, in which contribution of surface complexation accounted for 55.1% and 39.0%, respectively. Due to the large surface area and abundant newly formed MnO2, BC-Mn showed the maximum Pb sorption capacity of 1343 mmol kg-1, and its high removal efficiency appeared even at low pH value (pH = 2) and high initial Pb concentration (1.0 mol L-1). The contribution of cation exchange accounted for 97.4% of the Pb sorption by BC-Mn. These results suggested BC-Mn had great potential for Pb removal from aqueous solution, and the quantitative analyses of sorption mechanisms revealed the contribution of each mechanism and provided a basis for evaluating application prospects of biochars.

5.
Medicine (Baltimore) ; 98(44): e17679, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689786

RESUMO

To introduce the National Maternal Near Miss Surveillance System (NMNMSS) in detail and to report the composition of maternal near miss (MNM) in China.The NMNMSS was established by the National Health Commission at the end of 2010, covered over 400 health facilities from 30 provinces in China. The NMNMSS was designed to collect individual information for every pregnant woman admitted to obstetric department in the sampled health facilities. Cross tabulations and correlations were used to describe the distribution of population and sampled facilities in the NMNMSS, and to calculate the MNM mortality ratio for different complications and organ dysfunctions.The individual survey forms of 9,051,638 pregnant women were collected in the NMNMSS between 2012 and 2017. Compared with urban areas, there are very few well-quality medical resources in rural areas. Most women with pregnancy complications in rural areas can only be treated in Level 2 and lower hospitals. MNM in women with indirect obstetric complications received treatment more frequently in Level 3 hospital. The most common maternal complications in severe maternal outcomes (including maternal near miss and maternal death) are obstetrics hemorrhage (58.7%), hypertension disorder (28.0%), and severe anemia (20.6%). The overall MNM mortality ratio is 38:1. The MNM mortality ratios are lowest in amniotic fluid embolism, HIV/AIDS, heart disease, thrombophlebitis, and sepsis. For different organ dysfunctions, the ranks of the MNM mortality ratio from low to high are renal dysfunction, respiratory dysfunction, cardiovascular dysfunction, hepatic dysfunction, neurologic dysfunction, uterine dysfunction, coagulation dysfunction.The NMNMSS is a well-established hospital-based surveillance system for maternal complications in China. It can identify the maternal complications that need to improve health care immediately in China through a powerful longitudinal real-world evidence.

6.
J Bone Miner Res ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31691366

RESUMO

To detect painful vertebral fractures (VFs) in back pain populations at risk of osteoporosis, we designed a physical examination test (the Back Pain-Inducing Test (BPIT)) that included three movements: lying supine, rolling over, and sitting up. If back pain is induced during any of these movements, the result is defined as positive, thereby establishing a presumptive diagnosis of painful VFs. Pain severity is quantified using a self-reported numerical rating scale (NRS). The presence or absence of painful VFs is verified by whole-spine magnetic resonance imaging (MRI), the gold standard for final diagnosis. According to the standards for reporting diagnostic accuracy, a real-world, prospective and observational study was performed on 510 back pain patients (enrolled from a single institute) at risk of osteoporosis. The sensitivity, specificity, and accuracy of the BPIT for identifying painful VFs were 99.1% (95% confidence interval [CI], 97.5%-99.8%), 67.9% (95% CI, 60.4%-74.5%), and 89.0%, respectively. The positive and negative predictive values were 86.6% (95% CI, 82.9%-89.6%) and 97.4% (95% CI, 92.6%-99.3%), respectively. Cutoff NRS scores for lying supine, rolling over, and sitting up were 3, 0, and 2, respectively. The corresponding area under the receiver operating characteristic curves (AUROCs) of each movement was 0.898 (95% CI, 0.868-0.922), 0.884 (95% CI, 0.854-0.911), and 0.910 (95% CI, 0.882-0.933), respectively. Although the high prevalence of VFs in the enrolled cohort partially limits the external validity of the predictive value in the general population, we conclude that the BPIT is potentially effective for detecting painful VFs in back pain populations at risk of osteoporosis. This test may be used as a stratification tool in decision-making on subsequent imaging procedures: a negative BPIT rules out painful VFs and indicates that an MRI should be spared, while a positive BPIT means that an MRI is necessary and is likely to identify painful VFs.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31704169

RESUMO

OBJECTIVES: To monitor the serological typing of Haemophilus influenzae(Hi) in the lower respiratory tract infection in western Sichuan, China, the changes in beta-lactam resistance of the strains and the mechanism of beta-lactam resistance in these isolates over the past decade. METHODS: 54 strains of Nontypeable Haemophilus influenzae (NTHi) isolated from 2003 to 2004 and 220 strains of NTHi isolated from 2013 to 2014 were selected randomly. Hi strains were characterized by serological typing, and by PCR analysis of the p6, fucK and cap gene. The MIC values for ampicillin (AMP), Amoxicillin-clavulanic (AMC) acid and cefuroxime (CXM) were determined by broth microdilution susceptibility test. The TEM-1, ROB-1 and ftsI genes of the strain were sequenced; We compared the data obtained over a decade. The mechanisms of beta-lactam resistance and the effect of amino acid substitution of the ftsI gene on the MIC values of AMP, AMC and CXM were analyzed, respectively. RESULTS: 1. The MIC values of AMP, AMC and CXM of the NTHi strains isolated during 2013˜2014 were significantly higher than those of the strains collected during 2003˜2004 by rank sum test, p < 0.05. 2. BLA positive strains were 51.46% (141/274); gene sequencing showed that all 141 beta-lactamase positive strains were TEM-1 type. 3. There were 32 amino acid substitutions of the ftsI gene sequence and three of them had two amino acid substitutions in the NTHi isolated from 2013 to 2014. However, NTHi strains isolated from 2003 to 2004 had only the 9 amino acids substitutions (D350 N, M377I, A437S, G490E, A502 V,V511A, R517H and N526 K). 4. The results of rank sum test showed that only a few amino acids had no significant difference in the MIC values between the three beta-lactams. Ordered multiple classification logistic regression analysis showed that different amino acid replacement patterns of the ftsI gene had different effects on the MIC values of AMP, AMC and CXM, respectively. The main factors affecting the MIC value of AMP were in turn R517H (OR = 7.128), L389 F (OR = 6.999), N526 K (OR = 4.660) and D350 N (OR = 0.450); The main factor influencing the MIC value of AMC was an N526 K mutation (OR = 9.349);The main factors affecting the MIC value of CXM were the mutations S357 N (OR = 37.453) and N526 K (OR = 14.816). 5. Compared with the strains isolated from 2003 to 2004, the gBLNAR and gBLPAR strains isolated from 2013 to 2014 increased significantly from 12.96% (7/54), 9.26% (7/54) to 42.0% (84/220), 45.45% (100/220) respectively, p < 0.001. 6. Only 36.22% of the strains in the ftsI gene mutation fit the condition of group I ˜ III, and the group Ⅲ-like strain was 23.98% (47/196). In addition to M377I, S385 T, L389 F and N526 K mutations, all 47 NTHi strains also had amino acid substitution for D350 N and S357I. In other group, 13 NTHi strains had the same ftsI gene mutation pattern and 24 amino acid substitutions. CONCLUSIONS: Our results confirmed that Hi isolated from the lower respiratory tract of Western Sichuan in China from 2013 to 2014 were NTHi strains. Compared with ten years earler, beta-lactamase producing strains and beta-lactam resistant strains increased rapidly. The amino acid substitution of the ftsI gene was more complex and diversified. So far, although some progress has been made in the study of antibiotical resistance mechanism of NTHi strains, how to control the growth of NTHi resistant strains is still a challenge in China.

8.
Sci Total Environ ; 702: 134885, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31731121

RESUMO

Despite distinct roles of soil microbes in regulating carbon (C) respiration in diverse environments, it remains unclear whether microbial taxonomic and functional attributes can consistently predict soil C emissions across contrasting ecosystems. Here, we conducted a large-scale sampling event across two contrasting croplands (rice and wheat-corn crop rotation) to identify specific soil microbial phylotypes and functional genes associated with soil respiration rates. The results of structural equation modeling indicated that bacterial community composition had a strong link with C respiration rates in the two contrasting cropland types; however, this link was weaker for fungal communities. More importantly, we found that the relative abundances of bacterial Solirubrobacterales_480-2, Myxococcales_mle1-27 and fungal Westerdykella had consistently negative correlation with respiration rates across paddy and upland soils. We also identified taxa that are significantly correlated to C respiration in the paddy (e.g. Methylocaldum) and upland soils (e.g. Kribbella), respectively. Further, we found multiple associations between functional genes involved in microbial C metabolism and soil respiration rates. Our findings provide novel insights into understanding microbial predictors of soil CO2 emissions in diverse croplands, which have important implications for improving C emission predictions in terrestrial ecosystems.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31706653

RESUMO

Metal oxide/semiconductor heterostructures exhibit great potential for high-performance electronic device applications, but the interfacial defects resulting from lattice mismatch pose significant challenges to improving the performance of these devices. In this study, we reported a construction of a single crystal Ti2.5O3/GaAs heterostructure with minimum lattice mismatch between titanium sub-oxides and GaAs substrate. Low lattice mismatch values of 0.3% or 0.6% can be achieved along different orientations. Further experimental analyses demonstrate that high crystalline Ti2.5O3 (0 1 0) film can be grown layer by layer on GaAs (0 0 1) substrate with highly compatible interface. The defect-free interface significantly suppresses the diffusion of As and Ga ions, which impedes the formation of arsenic oxide and gallium oxide at the interface. Due to the high-quality Ti2.5O3 layer, the integrated BaTiO3(250 nm)/SrTiO3/Ti2.5O3(5 nm)/GaAs heterostructure exhibits an enhanced hysteresis loop with a remnant polarization of 9.85 µC/cm2 at 600 kV/cm and a small leakage current density of 1 × 10-5 A/cm2 at -500 kV/cm. The considerable advantage of this Ti2.5O3/GaAs heterostructure provides an example of integrating other functional oxides for GaAs with suppressed ion diffusion. It also provides a platform for fabricating different electronic devices with higher reliability and performance.

10.
J Am Chem Soc ; 141(46): 18630-18640, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674779

RESUMO

Cleavage of carbon-carbon bonds has been found in some important industrial processes, for example, petroleum cracking, and has inspired development of numerous synthetic methods. However, nonpolar unstrained C(aryl)-C(aryl) bonds remain one of the toughest bonds to be activated. As a detailed study of a fundamental reaction mode, here a full story is described about our development of a Ru-catalyzed reductive cleavage of unstrained C(aryl)-C(aryl) bonds. A wide range of biaryl compounds that contain directing groups (DGs) at 2,2' positions can serve as effective substrates. Various heterocycles, such as pyridine, quinoline, pyrimidine, and pyrazole, can be employed as DGs. Besides hydrogen gas, other reagents, such as Hantzsch ester, silanes, and alcohols, can be employed as terminal reductants. The reaction is pH neutral and free of oxidants; thus a number of functional groups are tolerated. Notably, a one-pot C-C activation/C-C coupling has been realized. Computational and experimental mechanistic studies indicate that the reaction involves a ruthenium(II) monohydride-mediated C(aryl)-C(aryl) activation and the resting state of the catalyst is a η4-coordinated ruthenium(II) dichloride complex, which could inspire development of other transformations based on this reaction mode.

11.
Andrology ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31743594

RESUMO

BACKGROUND: Whether androgen deprivation therapy (ADT) is associated with an increased risk of developing cardiovascular related disease is poorly defined. The aim of the present meta-analysis is to explore the relationship between ADT and the risk of cardiac events. METHOD: For this systematic review and meta-analysis, we searched databases from inception to April 2019 for randomized controlled trials (RCT) or observational studies that reported data on ADT administration and cardiac events incidence. The connection was evaluated through estimating relative risk ratio (RR) and 95% confidence intervals (CIs). RESULT: A significantly increased acute myocardial infarction (AMI) was detected in ADT group compared with control group; (RR = 1.19; 95% confidence interval CI, 1.02-1.39; P < .05). Significant difference between cardiovascular disease (CVD) and ADT was also observed, with summary RR = 1.25; 95% CI, 1.11-1.40; P < .05. Furthermore, our study also suggested ADT was not related to increased incidence of sudden cardiac death (SCD). (RR = 1.13; 95% CI, 0.92-1.38; P = .24); AMI and CVD were not connected with the duration of ADT. (AMI: RR = 1.31, 95%CI, 0.66-2.63, P = .44 for > 5 year group; CVD: RR = 1.12, 95% CI, 0.97-1.30; P = .12 for > 5 year group). In addition, the RR for risk of CVD was 1.28 (95% CI, 1.01-1.62 P < .05) for men with PCa on new hormonal agents. CONCLUSIONS: Pooled result demonstrated that ADT could significantly increase the risk of CVD and AMI, but not SCD. Various ADT modalities have different impact on cardiovascular disease risk in different level. Our meta-analysis also indicated that the long-term application of ADT is not associated with increased risk of AMI and CVD. Abiraterone and enzalutamide could significantly increase the incidence of cardiac events in patients who suffered from prostate cancer.

12.
Gene ; : 144243, 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31743768

RESUMO

BACKGROUND: Circulating microRNAs have become reliable sources of non-invasive biomarkers for cancer diagnosis. miRNA expression analysis in blood circulation for the identification of novel signatures might assist the early detection of nasopharyngeal carcinoma (NPC) patients. METHODS: In the screening stage, the Exiqon miRNA qPCR panel was applied for the selection of candidate miRNAs. Serum samples taken from 208 NPC patients and 238 healthy donors (as normal controls (NCs)) were assigned to into the following three stages (training (30 NPC VS. 30 NCs), testing (138 NPC VS. 166 NCs) and external validation stage (40 NPC VS. 42 NCs)) for further confirmation of differently expressed miRNAs using qRT-PCR. The identified miRNA signatures were further explored in tissue specimens (48 NPC VS. 32 NCs) and serum-derived exosomes samples (32 NPC VS. 32 NCs). RESULTS: Five miRNAs in serum including let-7b-5p, miR-140-3p, miR-192-5p, miR-223-3p and miR-24-3p were found to be significantly up-regulated in NPC patients compared to NCs. The five identified miRNAs were further combined into one panel and the areas under the receiver operating characteristic curve (AUCs) for three independent stages were 0.910 (training), 0.916 (testing) and 0.968 (external validation), respectively. miR-192-5p and miR-24-3p were consistently up-regulated in NPC tissues while let-7b-5p and miR-140-3p were conversely down-regulated. In serum-derived exosomes samples, no expression difference was observed between NPC patients and NCs. CONCLUSION: A five-miRNA signature was identified in serum to be potential biomarkers for NPC detection.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31744294

RESUMO

Here, the fluctuation of charge-transfer resistance at single reduce graphene oxide (rGO) microsheets with more redox-induced defects is unprecedentedly visualized using a perturbation electrochemiluminescence (ECL) imaging. This perturbation uses a short and low potential to recover defect-covered rGO microsheets slightly, and then, introduces a high potential to form more redox-induced defects resulting in an increase of charge-transfer resistance. Also, these defects at rGO microsheets enhance their catalytic feature and the resultant ECL intensity so that the temporal resolution in ECL imaging is improved to 30 ms. Aided by this fast imaging approach, the exponential decrease of ECL intensity at individual graphene microsheets after the oxidation is observed, which reflects the increase of their charge-transfer resistances. Since the charge-transfer resistance at electrode surfaces is mainly affected by the conductivity of electrode materials, the result provides the dynamic information to support the reduction of the electrical conductivity at graphene with more defects.

14.
J Hematol Oncol ; 12(1): 115, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31744509

RESUMO

BACKGROUND: The accurate information about lymphoma burden at national and provincial levels remains unknown in China. METHODS: Following the general analytical strategy used in GBD 2016, the age-, sex-, and province-specific incidence, mortality, and prevalence of lymphoma in China were analyzed. Trends in the incidence, mortality, prevalence, and disability-adjusted life years (DALYs) due to Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL) were assessed from 2006 to 2016. RESULTS: It was estimated that there were 75,400 new cases and 40,500 deaths of lymphoma in 2016 in China, of which 6900 new cases and 2900 deaths were due to HL, while 68,500 new cases and 37,600 deaths were due to NHL. The age-standardized incidence rate (ASIR), mortality rate (ASMR), and prevalence rate (ASPR) per 100,000 were 0.46, 0.19, and 1.75 for HL, and 4.29, 2.45, and 14.9 for NHL, respectively. An upward trend with age in incidence and mortality was observed. Males had higher incidence and mortality rates than females in all age groups. Sociodemographic index had a correlation with the ASIR (r = 0.75), ASMR (r = - 0.74), ASPR (r = 0.84), and age-standardized DALYs (r = - 0.75) of HL, as well as with the ASIR (r = 0.80), ASPR (r = 0.83), and age-standardized DALYs (r = - 0.33) of NHL. From 2006 to 2016, the age-standardized DALYs of HL decreased significantly, while the age-standardized DALYs of NHL increased from 2006 to 2013 and remained stable from 2013 to 2016. CONCLUSIONS: The burden of lymphoma in China showed unexpected patterns varied by sex, age, and provinces, with an increased trend of NHL and a decreased trend of HL from 2006 to 2016.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31677789

RESUMO

WW domain containing E3 Ub-protein ligase 2 (WWP2) plays an important role in tumor progression as an E3 ligase of PTEN. Here, we investigated the role of WWP2 in gastric cancer (GC). We found that WWP2 is overexpressed in GC tissues, which is closely related to poor prognosis of GC patients. Using a WWP2-shRNA lentivirus expressing system, we established WWP2 stable-knockdown GC cell lines and found that knockdown of WWP2 inhibits the proliferation of GC cells both in vitro and in vivo. Also, WWP2 silencing induced the up-regulation of PTEN protein level and down-regulation of AKT phosphorylation level. We further investigated the role of PTEN in this regulating process by performing rescue assay and found that PTEN is essential for WWP2-mediated regulation of GC cells proliferation. Taken together, our results demonstrated that WWP2 promotes proliferation of GC cells by downregulating PTEN, which may provide new therapeutic targets for GC.

16.
Cell Prolif ; : e12700, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667976

RESUMO

OBJECTIVES: Long non-coding RNA (lncRNA) MATN1-AS1 is a newfound lncRNA that has been rarely explored in cancers. Herein, we would like to investigate its role in glioma. MATERIALS AND METHODS: qRT-PCR was conducted to examine gene expression in glioma. Then, MTT assay, colony formation assay and flow cytometry analysis were applied to evaluate the function of MATN1-AS1 on glioma cells. Western blot was performed to measure the protein levels of genes. Besides, the luciferase reporter assay, RNA pull-down assay, RIP assay and Spearman's correlation analysis were also performed as needed. RESULTS: Firstly, a data from TCGA showed that MATN1-AS1 might be largely implicated in glioma. Meanwhile, MATN1-AS1 upregulation confirmed in glioma predicted poor clinical outcomes. Functionally, MATN1-AS1 knockdown restrained cell proliferation but stimulated apoptosis in vitro and repressed tumour growth in vivo. Mechanistic investigations validated that MATN1-AS1 functioned as a ceRNA for miR-200b/c/429 to upregulate CHD1 which was also verified to exert a growth-promoting role in glioma cells here. Importantly, both CHD1 overexpression and miR-200b/c/429 inhibition could rescue the obstructive role of MATN1-AS1 silence in glioma cells. CONCLUSIONS: MATN1-AS1 promotes glioma progression through regulating miR-200b/c/429-CHD1 axis, suggesting MATN1-AS1 as a probable target for glioma treatment.

17.
Int J Cardiol ; 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31668660

RESUMO

AIMS: To recapitulate progressive human dilated cardiomyopathy (DCM) and heart block in the Lmna R225X mutant mice model and investigate the molecular basis of LMNA mutation induced cardiac conduction disorders (CD); To investigate the potential interventional impact of exercise endurance. METHODS AND RESULTS: A Lmna R225X knock-in mice model in either heterozygous or homozygous genotype was generated. Electrical remodeling was observed with higher occurrence of AV block from neonatal and aged mutant mice as measured by surface electrocardiogram and atrio-ventricular Wenckebach point detection. Histological and molecular profiles revealed an increase in apoptotic cells and activation of caspase-3 activities in heart tissue. Upon aging, extracellular cellular matrix (ECM) remodeling appeared with accumulation of collagen in Lmna R225X mutant hearts as visualized by Masson's trichrome stain. This could be explained by the upregulated ECM gene expression, such as Fibronectin: Fn1, collagen: Col12a1, intergrin: Itgb2 and 3, as detected by microarray gene chip. Also, endurance exercise for 3 month improved the ventricular ejection fraction, attenuated fibrosis and cardiomyocytes apoptosis in the aged mutant mice. CONCLUSIONS: The mechanism of LMNA nonsense mutation induced cardiac conduction defects through AV node fibrosis is due to upregulated ECM gene expression upon activation of cardiac apoptosis. Lmna R225X mutant mice hold the potential for serving as in vivo models to explore the mechanism and therapeutic methods for AV block or myopathy associated with the aging process.

19.
CNS Neurosci Ther ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730272

RESUMO

OBJECTIVE: Impairment of basal ganglia (BG)-thalamo-cortical circuit causes various symptoms of Parkinson's disease (PD). We investigated the functional connectivity (FC) patterns of putamen among PD subtypes and healthy control (HC) and explored their clinical significance. METHODS: A total of 16 patients with tremor-dominant (TD) PD, 23 patients with postural instability and gait difficulty-dominant (PIGD) PD, and 31 HC that underwent functional magnetic resonance imaging were observed. Voxel-wise FC analysis was performed by computing correlation between bilateral putamen and other voxels within the brain. Correlation analysis was performed between FC strength and clinical symptoms. RESULTS: Compared with PIGD group, TD group showed increased FC between left putamen and right cerebellum lobule VI and cerebellum crus I, then we compared the cerebellum FC difference among the three groups. The cerebellum lobule VI FC difference was mainly involved in motor related cortex, and the cerebellum crus I FC difference was related to cognition areas. While compared with HC, TD and PIGD groups both had significant FC difference brain areas correlated with motor and cognition symptoms. The connectively of putamen and right cerebellum lobules VI and I showed positive correlation with tremor and Montreal Cognitive Assessment degree of scores, respectively. The connectivity of putamen and sensorimotor cortex had negative correlation with PIGD scores. CONCLUSIONS: The altered connectivity of BG-cortical circuit in patients with PD was related to PIGD symptoms. Motor and cognitive impairments declined slower in patients with TD PD, which may be related to increased functional connectivity between putamen and cerebellum.

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