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1.
Dev Comp Immunol ; 114: 103833, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32818607

RESUMO

Food deprivation is a severe stress across multiple fields and challenged to organismal development and immune system. Here, adult male zebrafish were used to investigate the starvation stress on organismal development, spermatogenesis, testicular inflammation and apoptosis. Results showed that the biological indexes, blood parameters, and RNA/DNA ratio in testis dramatically decreased after 1-3 weeks of starvation. The testicular architecture was impaired and the spermatogenesis was retarded with increased proportions of spermatogonia and spermatocytes, and decreased proportion of spermatozoa in the starved fish. The mRNA expressions of amh and sycp3 were downregulated, the retinoic acid content increased at later stage of starvation through the transcriptional regulation of aldh1a2 and cyp26a1. Besides, the immune response was elevated with upregulated mRNA and protein expressions of TNF-α, IL-6, and IL-1ß, which indicated the inflammation of opportunistic risk in testis. The apoptotic activity was stimulated, accompanied by differentially upregulated expressions of baxa, casp9, casp3, casp2, and decreased ratio of Bcl-2/Bax in the attenuate testis. Taken together, our findings revealed that the stress responses of testicular development, inflammatory and apoptotic activities in male zebrafish under starvation and pointed out the susceptibility of fish gonad to food fluctuation.

2.
Exp Cell Res ; : 112392, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33227315

RESUMO

BACKGROUND: The proliferation of pulmonary arterial smooth muscle cells (PASMCs) and subsequent pulmonary vascular remodeling leads to pulmonary arterial hypertension (PAH). Understanding the underlying mechanisms and identifying molecules that can suppress PASMCs proliferation is critical for developing effective pharmacological treatment. We previously showed that plasminogen activator inhibitor-2 (PAI-2) inhibited human PASMC (hPASMCs) proliferation in vitro. However, its inhibitory effect on PAH remains to be determined, and the mechanism remains to be illustrated. METHODS: We compared serum PAI-2 levels between PAH patients and healthy controls, and examined the correlation between PAI-2 level and disease severity. In monocrotaline-induced PAH rats, we examined the effects of exogenous PAI-2 administration on pulmonary vascular remodeling and PAH development. The effect of PAI-2 and potential mechanisms was further examined in cultured hPASMCs. RESULTS: The serum PAI-2 was decreased in PAH patients compared with controls. PAI-2 level was negatively correlated with mean pulmonary arterial pressure and estimated systolic pulmonary arterial pressure in ultrasonic cardiogram, while positively correlated with 6-min walking distance. In rats, administration of exogenous PAI-2 significantly reversed monocrotaline-induced PAH, as indicated by the decrease in right ventricle systolic pressure, right ventricular hypertrophy index and percent media thickness of pulmonary arterioles. Further mechanistic investigation in hPASMCs showed that PAI-2 inhibited cell proliferation by preventing the activation of PI3K/Akt and ERK pathways. CONCLUSION: PAI-2 is downregulated in PAH patients. PAI-2 attenuates PAH development by suppressing hPASMCs proliferation via the inhibition of PI3K/Akt and ERK pathways. PAI-2 may serve as a potential biomarker and therapeutic target for PAH.

3.
J Chem Phys ; 153(18): 184101, 2020 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-33187447

RESUMO

We study nonideal mixing effects in the regime of warm dense matter (WDM) by computing the shock Hugoniot curves of BN, MgO, and MgSiO3. First, we derive these curves from the equations of state (EOS) of the fully interacting systems, which were obtained using a combination of path integral Monte Carlo calculations at high temperature and density functional molecular dynamics simulations at lower temperatures. We then use the ideal mixing approximation at constant pressure and temperature to rederive these Hugoniot curves from the EOS tables of the individual elements. We find that the linear mixing approximation works remarkably well at temperatures above ∼2 × 105 K, where the shock compression ratio exceeds ∼3.2. The shape of the Hugoniot curve of each compound is well reproduced. Regions of increased shock compression, which emerge because of the ionization of L and K shell electrons, are well represented, and the maximum compression ratio of the Hugoniot curves is reproduced with high precision. Some deviations are seen near the onset of the L shell ionization regime, where ionization equilibrium in the fully interacting system cannot be well reproduced by the ideal mixing approximation. This approximation also breaks down at lower temperatures, where chemical bonds play an increasingly important role. However, the results imply that the equilibrium properties of binary and ternary mixtures in the regime of WDM can be derived from the EOS tables of the individual elements. This significantly simplifies the characterization of binary and ternary mixtures in the WDM and plasma phases, which otherwise requires large numbers of more computationally expensive first-principles computer simulations.

4.
Genes (Basel) ; 11(11)2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33158173

RESUMO

Metastasis and recurrence are the main causes of lung adenocarcinoma patients' death. Lymphatic metastasis is the main way of non-small cell lung cancer (NSCLC) metastasis. C-C chemokine receptor type 7 (CCR7) overexpression has been demonstrated to mediate occurrence and progression of NSCLC. Moreover, Chemokine ligand 21 (CCL21) was used to activate CCR7. The CCR7-CCL21 axis is one of the most common "chemokine-receptor" modes of action in the development and metastasis of multiple tumors. However, the role of the CCR7-CCL21 axis in lymphatic metastasis of NSCLC is poorly understood. The study was conducted to investigate the molecular mechanism underlying CCR7-CCL21 axis-mediated lymphatic metastasis of NSCLC A549 cells. Tumor necrosis factor α (TNF-α) could regulate the tumor microenvironment balance by promoting chemokine secretion. Our study demonstrated that TNF-α promoted CCL21 production in human lymphatic endothelial cells (HLEC). Results further showed that TNF-α significantly activated the NF-κB pathway in HLEC. NF-κB pathway inhibition with ammonium pyrrolidinedithiocarbamate (PDTC) caused a significant decrease in CCL21 secretion, suggesting that TNF-α-induced CCL21 secretion in HLEC was through NF-κB pathway. Co-culture of A549 cells and TNF-α-treated HLEC confirmed that the metastasis of A549 cells was enhanced, meanwhile, apoptosis-related proteins were hardly affected. The data proved that a co-culture system prevented cell apoptosis while inducing the lymphatic metastasis of A549 cells. However, the situation was reversed after neutralizing CCL21 expression, suggesting that TNF-α-induced CCL21 secretion in HLEC is involved in A549 cells metastasis. Collectively, our finding demonstrated that NF-κB pathway-controlled CCL21 secretion of HLEC contributing to the lymphatic metastasis of A549 cells via the CCR7-CCL21 axis, validating the CCR7-CCL21 axis as a potential target to inhibit metastasis of NSCLC.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33177378

RESUMO

PURPOSE: The aim of this study was to validate and compare the prognostic performance of the albumin-bilirubin (ALBI) grade, platelet-albumin-bilirubin (PALBI) grade, Child-Pugh (CP) grade, and Model for End-Stage Liver Disease (MELD) score in predicting the 1-year variceal rebleeding probability using artificial intelligence for patients with cirrhosis and variceal bleeding undergoing early transjugular intrahepatic portosystemic shunt (TIPS) procedures. MATERIALS AND METHODS: This dual-center retrospective study included two cohorts, with patients enrolled between January 2016 and September 2018 in the training cohort and January 2017 and September 2018 in the validation cohort. In the training cohort, independent risk factors associated with the 1-year variceal rebleeding probability were identified using univariate and multivariate logistic analyses. ALBI-, PALBI-, Child-Pugh-, and MELD-based nomograms and an artificial neural network (ANN) model were established and validated internally in the training cohort and externally in the validation cohort, which included patients with variceal bleeding who were treated with preventive TIPS. RESULTS: A total of 259 patients were included. The median follow-up periods were 24.1 and 18.9 months, and the 1-year variceal rebleeding rates were 12.3% (14/114) and 10.3% (15/145) in the training and validation cohorts, respectively. In the training cohort, all four variables were identified as independent risk factors. Four nomograms were then established and showed comparable prognostic performances after internal (C-index: 0.879, 0.829, 0.874, and 0.798) and external (C-index: 0.720, 0.719, 0.718, and 0.703) validation. The ANN demonstrated that these four variables had comparable importance in predicting the 1-year variceal rebleeding probability. CONCLUSION: None of the four variables are optimal in predicting the 1-year variceal rebleeding probability for patients with cirrhosis and variceal bleeding undergoing early TIPS.

6.
J Clin Neurosci ; 81: 252-258, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33222925

RESUMO

OBJECTIVE: To assess the relationship between sleep duration and risk of rupture of intracranial aneurysms (IAs). METHODS: According to our inclusion and exclusion criteria, 683 patients admitted to Beijing Tiantan Hospital were included in this study. There were 201 patients in the ruptured group and 482 patients in the unruptured group. Sleep duration was divided into three levels: ≥8 h (long), 6-8 h (normal), ≤6 h (short). Correlation between different sleep duration and rupture of IAs was evaluated by univariate and multivariate regression analysis. RESULTS: The results of multivariate analysis demonstrated that there was a statistical difference between sleep duration of ≤6 h and sleep duration ≥8 h (OR = 1.76, CI = [1.08-2.87], p = 0.025). There was no statistically significant difference between the group with sleep duration of 6-8 h and sleep duration of ≥8 h (OR = 1.04, CI = [0.65-1.67], p = 0.857). CONCLUSION: Short sleep duration (≤6 h) may be related to the rupture of intracranial aneurysms. The reason for this correlation is not yet clear. We suspect that it may be caused by a series of physiological changes caused by reduced sleep.

7.
Sci Adv ; 6(47)2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33219028

RESUMO

Controlling the interlayer twist angle offers a powerful means for tuning the electronic properties of two-dimensional (2D) van der Waals materials. Typically, the electrical conductivity would increase monotonically with decreasing twist angle owing to the enhanced coupling between adjacent layers. Here, we report a nonmonotonic angle-dependent vertical conductivity across the interface of bilayer graphene with low twist angles. More specifically, the vertical conductivity enhances gradually with decreasing twist angle up to a crossover angle at θc ≈ 5°, and then it drops notably upon further decrease in the twist angle. Revealed by density functional theory calculations and scanning tunneling microscopy, the abnormal behavior is attributed to the unusual reduction in average carrier density originating from local atomic reconstruction. The impact of atomic reconstruction on vertical conductivity is unique for low-angle twisted 2D van der Waals materials and provides a strategy for designing and optimizing their electronic performance.

8.
JMIR Mhealth Uhealth ; 8(11): e19869, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33141092

RESUMO

BACKGROUND: Intensive lifestyle modifications have proved effective in preventing type 2 diabetes mellitus (T2DM), yet the efficiency and effectiveness of these modifications need to be improved. Emerging social media interventions are considered useful in promoting these lifestyles; nevertheless, few studies have investigated the effectiveness of combining them with behavior theory. OBJECTIVE: This study aims to examine the effectiveness of a 6-month mobile-based intervention (DHealthBar, a WeChat applet) combined with behavioral theory compared with a printed intervention in improving dietary behaviors, physical activity, and intention to change these behaviors among populations at high risk for T2DM. METHODS: Participants aged 23 to 67 years were recruited offline in Beijing, China, and were randomized into the intervention group or the control group, which received educational content via DHealthBar or a printed handbook, respectively. Educational materials were culturally tailored recommendations on improving dietary behaviors, physical activity, and intention to change based on the transtheoretical model. Participants in the intervention arm received push notifications twice per week on WeChat and had access to the educational content for the 6-month study period. Participants in the control arm received the same intervention content through printed materials. The outcomes of participants' behavior change, intention to change behavior, and anthropometric characteristics were collected via online measuring tools at baseline, 3 months, and 6 months. RESULTS: In this study, 79 enrolled individuals completed baseline information collection (control: n=38 vs intervention: n=41), and 96% (76/79) completed the 6-month follow-up visit. Attrition rates did not differ significantly between the 2 groups (χ21=0.0, P=.61). Baseline equivalence was found. Participants in both groups reported a statistically significant decrease in energy intake at the 2 follow-up assessments compared with baseline (3 months, control: exp[ß]=0.83, 95% CI 0.74-0.92 vs intervention: exp[ß]=0.76, 95% CI 0.68-0.85; 6 months, control: exp[ß]=0.87, 95% CI 0.78-0.96 vs intervention: exp[ß]=0.57, 95% CI 0.51-0.64). At 6 months, a significantly larger decrease was observed in the intervention group in energy, fat, and carbohydrate intake, accompanied with a significantly larger increase in moderate-intensity physical activity compared with the control group (energy: exp[ß]=0.66, 95% CI 0.56-0.77; fat: exp[ß]=0.71, 95% CI 0.54-0.95; carbohydrates: exp[ß]=0.83, 95% CI 0.66-1.03; moderate-intensity physical activity: exp[ß]=2.05, 95% CI 1.23-3.44). After 6 months of the intervention, participants in the intervention group were more likely to be at higher stages of dietary behaviors (exp[ß]=26.80, 95% CI 3.51-204.91) and physical activity (exp[ß]=15.60, 95% CI 2.67-91.04) than the control group. CONCLUSIONS: DHealthBar was initially effective in improving dietary behavior, physical activity, and intention to change these behaviors among populations who were at high risk of developing T2DM, with significant differences in the changes of outcomes over the 6-month intervention period. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000032323; https://tinyurl.com/y4h8q4uf.

9.
BMC Musculoskelet Disord ; 21(1): 743, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33183281

RESUMO

BACKGROUND: Surgeons recognize that using percutaneous kyphoplasty (PKP) under local anesthesia to treat osteoporotic vertebral fracture (OVF) prevents interference with the general situation of elderly patients suffering from multiple organ dysfunction. Surgeons can directly assess whether nerve injury occurs while the patient is awake. However, when patients with multiple osteoporotic vertebral fractures (m-OVFs) receive local anesthesia, fluoroscopy time often has to be increased, the operative time has to be extended, or the operation has to be terminated because of discomfort related to body posture. No relevant study has thus far been conducted on the type of anesthesia to administer to patients undergoing PKP for m-OVFs. This study aimed to determine which of the two types of anesthesia is more suitable for PKP for m-OVFs. METHODS: A retrospective study was conducted involving 159 patients who underwent PKP for m-OVFs from January 2016 to January 2020; 81 patients underwent PKP under general anesthesia (Group G), and 78 patients underwent PKP under local anesthesia (Group L). Clinical and adverse events were compared between the two groups. RESULTS: The intraoperative mean arterial pressure, average heart rate, average fluoroscopy times of each vertebral body, and operative time were less in Group G than in Group L. The visual analog scale (VAS) score was significantly lower after than before the operation. The anterior vertebral height (AVH), middle vertebral height (MVH), and kyphotic angle (KA) were significantly improved in both groups postoperatively. The improvement in VAS score, AVH, MVH, and KA in Group G were higher than those in Group L. No significant difference in the incidence of complications was observed between the two groups. CONCLUSION: PKP under either general anesthesia or local anesthesia was reliable. Compared with PKP under local anesthesia, PKP under general anesthesia could more reliably maintain the stability of vital signs, alleviate preoperative pain in patients, and attain a better orthopedic effect. Moreover, the latter does not increase the complications of patients with m-OVFs. However, the high medical expense of PKP under general anesthesia is a factor to consider when choosing the type of anesthesia.

10.
Cell Transplant ; 29: 963689720969167, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33231090

RESUMO

This study aimed to explore the characteristics of TGFBR1-epidermal growth factor receptor (EGFR)-CTNNB1-CDH1 axis in regulating the invasion and migration in lung cancer. Using the small interfering RNA technology, EGFR was silenced in H2170 and H1299 cells. Then, the colony formation, migration, and invasion abilities were detected using colony-forming assay and transwell assay. Moreover, the mRNA expression of smad2, smad3, CTNNB1, and CDH1, and the protein expression of TGFBR1, CDH1, and TCF were determined using the real-time polymerase chain reaction and western blotting. The results showed that silencing EGFR could significantly decrease the colony-forming ability in H2170 and H1299. Knocking down EGFR could significantly inhibit the invasion and migration ability of H2179 and H1299. Inhibiting the expression of EGFR could significantly decrease the expression of smad2, smad3, CDH1, and CTNNB1, with all P-values <0.05. In addition, silencing EGFR could markedly decrease the expression of TGFBR1 and CDH1 in H1299 and H2170, with all P-values <0.05. In conclusion, silencing EGFR could significantly regulate the progression of lung cancer via TGFBR1-EGFR-CTNNB1-CDH1 axis in Wnt signaling pathway.

11.
Vet Microbiol ; 251: 108861, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-33059276

RESUMO

Since 2017, duck spleen necrosis caused by new variant duck orthoreovirus (N-DRV) infection had been observed in several provinces in China. This disease retards the growth and development of ducks, thereby reducing feed return rate. N-DRV infection causes damage to duck spleen and other immune organs, leading to immunosuppression and susceptibility to other pathogens. In this study, we successfully constructed a breeding duck artificial infection model and found that N-DRV infection can cause pathologic changes, such as ovarian hemorrhage, follicle atrophy, and fallopian tube bleeding in breeding ducks, resulting in significantly reduced fertilization rate and egg hatching rate. Viral RNA was present in egg vitelline membrane, duck embryo, and duckling's spleen samples, as determined through quantitative polymerase chain reaction (qPCR). Autopsy revealed obvious pathologic changes in the spleen and other organs, although there were no obvious early clinical symptoms observed in ducklings. Sequence distance and phylogenetic analysis confirmed that N-DRV-SD19 re-isolated from the spleen samples of ducklings was consistent with the strain N-DRV-XT18 used for infecting breeding ducks. The findings in this study confirmed that N-DRV can be vertically transmitted through eggs, which provide an important reference for the disease prevention and control.

12.
Mol Plant Microbe Interact ; : MPMI07200201R, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33021883

RESUMO

Ciboria shiraiana causes hypertrophy sorosis scleroteniosis in mulberry trees, resulting in huge economic losses, and exploring its pathogenic mechanism at a genomic level is important for developing new control methods. Here, genome sequencing of C. shiraiana based on PacBio RSII and Illumina HiSeq 2500 platform as well as manual gap filling was performed. Synteny analysis with Sclerotinia sclerotiorum revealed 16 putative chromosomes corresponding to 16 chromosomes of C. shiraiana. Screening of rapid-evolution genes revealed that 97 and 2.4% of genes had undergone purifying selection and positive selection, respectively. When compared with S. sclerotiorum, fewer secreted effector proteins were found in C. shiraiana. The number of genes involved in pathogenicity, including secondary metabolites, carbohydrate active enzymes, and P450s, in the C. shiraiana genome was comparable with that of other necrotrophs but higher than that of biotrophs and saprotrophs. The growth-related genes and plant cell-wall-degradation-related genes in C. shiraiana were expressed in different developmental and infection stages, and may be potential targets for prevention and control of this pathogen. These results provide new insights into C. shiraiana pathogenic mechanisms, especially host range and necrotrophy features, and lay the foundation for further study of the underlying molecular mechanisms.

13.
Thromb Res ; 196: 500-509, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33091704

RESUMO

Platelets play such an important role in the process of thrombosis that patients with thrombocytopenia generally have an increased risk of bleeding. However, abnormal thrombotic events can sometimes occur in patients with thrombocytopenia, which is unusual and inexplicable. The treatments for thrombocytopenia and thromboembolism are usually contradictory. This review introduces the mechanisms of thromboembolism in patients with different types of thrombocytopenia and outlines treatment recommendations for the prevention and treatment of thrombosis. According to the cause of thrombocytopenia, this article addresses four etiologies, including inherited thrombocytopenia (Myh9-related disease, ANKRD26-associated thrombocytopenia, Glanzmann thrombasthenia, Bernard-Soulier syndrome), thrombotic microangiopathy (thrombotic thrombocytopenic purpura, atypical hemolytic uremic syndrome, hemolytic uremic syndrome, Hemolysis Elevated Liver enzymes and Low Platelets syndrome, disseminated intravascular coagulation), autoimmune-related thrombocytopenia (immune thrombocytopenic purpura, antiphospholipid syndrome, systemic lupus erythematosus), and acquired thrombocytopenia (Infection-induced thrombocytopenia and drug-induced thrombocytopenia, heparin-induced thrombocytopenia). We hope to provide more evidence for clinical applications and future research.

14.
Artigo em Inglês | MEDLINE | ID: mdl-33090662

RESUMO

Photocatalytic N 2 fixation to NH 3 with water as the reducing agent represents a promising future strategy for ammonia synthesis, motivating the discovery of efficient photocatalysts that offer high sunlight utilization and catalytic efficiency to N 2 fixation. Cu 2 O, a low-cost, visible light-responsive semiconductor photocatalyst represents an ideal candidate for visible light-driven photocatalytic reduction of N 2 to NH 3 from the viewpoint of thermodynamics, but remaining unexplored in this field yet. Noticeably, a majority of Cu 2 O photocatalysts synthesized to date with large lateral sizes (typically tens to hundreds of nanometers) generally suffer from severe electron-hole recombination and limited surface sites, restricting its photocatalytic activity for potential N 2 fixation. Ultrafine photocatalysts with lateral dimensions ~1-3 nm offer distinct advantages over conventional nanoparticle-based photocatalysts in this context, though the controlled synthesis of ultrafine photocatalysts remains challenging. Herein, we report the successful synthesis of uniformly sized and ultrafine Cu 2 O platelets with lateral size < 3 nm via the in-situ topotactic reduction of a Cu(II)-containing layered double hydroxide with ascorbic acid. The supported ultrafine Cu 2 O offered excellent performance and stability for the visible light-driven photocatalytic reduction of N 2 to NH 3 (the Cu 2 O-mass-normalized rate as high as 4.10 mmol gCu 2 O -1 h -1 at λ > 400 nm), with the origin of the high activity being long-lived photo-excited electrons in trap states, an abundance of exposed active sites and the underlying support structure. This work guides the future design of ultrafine catalysts for NH 3 synthesis and other applications.

15.
Biomed Res Int ; 2020: 7351876, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33123585

RESUMO

Purpose: To investigate the predictive value of changes in LAA size and function for cardiogenic stroke (CS) in patients with NVAF by coronary CTA examination. Materials and Method. 179 patients with NVAF were selected and grouped according to the outbreak of acute ischemic stroke and TIA within 2 years after coronary CTA examination. Those who met the criteria for CS were selected as cases (87 patients), and those neither stroke nor TIA as controls (92 patients). LAA size of selected patients was measured and data postprocessing was performed. The differences of baseline data and LAA parameters between groups were analyzed. The impacts of BMI, hyperlipidemia, the duration of AF, the LAAOA Index, and the LAAEF on CS were assessed by binary logistic regression. The predictive abilities of LAAOA Index, LAAEF, and the combined predictor were assessed by ROC curves. Results: Proportions of BMI ≥ 25, prevalence of hyperlipidemia, duration of AF, and LAAODmax, LAAODmin, LAAOA, LAAVmax, and LAAVmin with their correction index were greater in cases than controls. The LAAEF was lower in cases than that in controls. The binary logistic regression model showed an increase in LAAOA Index (P = 0.005) and a decrease in LAAEF (P < 0.001) were independent risk factors for CS. ROC curve analysis showed that the optimal cutoff values of LAAOA Index and LAAEF to predict CS were 3.16 cm2/m2 and 38.71%, with AUC value of 0.712 and 0.734, respectively. The LAAOA Index-LAAEF combined predictor (AUC value = 0.786) was likely superior to either LAAOA Index or LAAEF. Conclusions: Coronary CTA can provide additional valuable parameters, as a by-product of coronary artery assessment without additional radiation dose, for the risk assessment of CS in patients with NVAF. Coronary CTA may make up for the limitation of single indicator of CHA2DS2-VASc in guiding anticoagulation program, to reduce the incidence of embolism and bleeding events.

16.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(5): 537-540, 2020 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-33085238

RESUMO

OBJECTIVE: To study the stress distribution under dynamic loading in the presence or absence of an abutment buffer layer by using three-dimensional finite element analysis. METHODS: A three-dimensional solid geometric model of an implant in a human mandible was established on the basis of CT scan data. A buffer-free abutment prosthesis and a buffer-abutment abutment prosthesis were installed above the implant. The buffer layer was made of high-density polyethylene. A vertical load of 200 N and a horizontal load of 100 N (45°) were concentrated on the centers of the implant restorations of the two groups. Stresses on the implant neck and body, abutment neck and body, central bolt neck and body, and bone interface were compared via three-dimensional finite element analysis. RESULTS: Stresses on the implant neck and body, abutment neck and body, central bolt neck and body, and bone interface on the abutment with a buffer layer were significantly lower than those on the abutment without a buffer layer. CONCLUSIONS: The increase in the buffer layer of the abutment neck significantly reduced stress on the implant neck, abutment, central bolt neck, and bone interface.


Assuntos
Dente Suporte , Implantes Dentários , Análise do Estresse Dentário , Análise de Elementos Finitos , Humanos , Estresse Mecânico
17.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(5): 541-545, 2020 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-33085239

RESUMO

OBJECTIVE: This study aims to evaluate the clinical effect of oral repair membrane and ß-tricalcium phosphate (ß-TCP) on the treatment of jaw cyst. METHODS: A retrospective analysis was performed on 81 cases of jaw cysts, and clinical data were collected for the comparison of traditional surgical curettage (group A, 27 cases), biofilm covering bone wounds after curettage (group B, 27 cases), and ß-TCP filling combined with biofilm covering. RESULTS: No recurrence occurred in 81 patients, and no significant difference in preoperative CT value among the three groups (P<0.05). Follow-up CT reexamination 3, 6, and 12 months after operation showed significant differences among the three groups of CT values (P<0.05). Group C was better than Group B or Group A (P<0.05). CONCLUSIONS: In traditional jaw cyst curettage, the application of biofilm exhibited good osteogenesis effect, and the combined application of ß-TCP and biofilm exerted a better effect.


Assuntos
Fosfatos de Cálcio , Cistos Maxilomandibulares , Humanos , Osteogênese , Estudos Retrospectivos
18.
J Phys Chem Lett ; : 9587-9595, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33119309

RESUMO

The magnetic coupling interaction of Mn2+-Mn2+ in Mn2+-included phosphors could induce a shorter emission decay time, compared with that of isolated Mn2+, which could overcome the photoluminescence (PL) saturation when stimulated by a high photon flux due to the long lifetime of the Mn2+ excited state. However, few studies have directly proved the Mn2+-Mn2+ coupling effect on the PL decay. In this paper, the effect on PL of CsMnCl3 (CMC) and its hydrates is revealed by photomagnetism results, excluding the interference effects of site symmetry and phonon energy. The antiferromagnetic interaction of the CMC is larger when Mn2+ at a photoexcited state than at a dark state, which is contrary to the hydrates with weak Mn2+-Mn2+ interaction. This research not only helps researchers to understand the fundamental optical process but also is instructive for designing high performance Mn2+-doped phosphors in the field of displays and lighting.

19.
Aging (Albany NY) ; 12(20): 20047-20068, 2020 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-33099540

RESUMO

Lung cancer remains the most lethal cancer worldwide because of its high metastasis potential. Epithelial-mesenchymal transition (EMT) is known as the first step of the metastasis cascade, but the potential regulatory mechanisms of EMT have not been clearly established. In this study, we first found that low CUEDC1 expression correlated with lymph node metastasis in non-small cell lung cancer (NSCLC) patients using immunohistochemistry (IHC). CUEDC1 knockdown promoted the metastasis of NSCLC cells and EMT process and activated TßRI/Smad signaling pathway. Overexpression of CUEDC1 decreased the metastatic potential of lung cancer cells and inhibited the EMT process and inactivated TßRI/Smad signaling pathway. Immunoprecipitation (IP) assays showed that Smurf2 is a novel CUEDC1-interacting protein. Furthermore, CUEDC1 could regulate Smurf2 expression through the degradation of Smurf2. Overexpression of Smurf2 abolished CUEDC1 knockdown induced-EMT and the activation of TßRI/Smad signaling pathway, while siRNA Smurf2 reversed CUEDC1 overexpression-mediated regulation of EMT and TßRI/Smad signaling pathway. Additionally, CUEDC1 inhibited proliferation and promoted apoptosis of NSCLC cells. In vivo, CUEDC1-knockdown cells promoted metastasis and tumor growth compared with control cells. In conclusion, our findings indicate that the crucial role of CUEDC1 in NSCLC progression and provide support for its clinical investigation for therapeutic approaches.

20.
Nat Nanotechnol ; 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046843

RESUMO

Electrets are dielectric materials that have a quasi-permanent dipole polarization. A single-molecule electret is a long-sought-after nanoscale component because it can lead to miniaturized non-volatile memory storage devices. The signature of a single-molecule electret is the switching between two electric dipole states by an external electric field. The existence of these electrets has remained controversial because of the poor electric dipole stability in single molecules. Here we report the observation of a gate-controlled switching between two electronic states in Gd@C82. The encapsulated Gd atom forms a charged centre that sets up two single-electron transport channels. A gate voltage of ±11 V (corresponding to a coercive field of ~50 mV Å-1) switches the system between the two transport channels with a ferroelectricity-like hysteresis loop. Using density functional theory, we assign the two states to two different permanent electrical dipole orientations generated from the Gd atom being trapped at two different sites inside the C82 cage. The two dipole states are separated by a transition energy barrier of 11 meV. The conductance switching is then attributed to the electric-field-driven reorientation of the individual dipole, as the coercive field provides the necessary energy to overcome the transition barrier.

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