Composition-dependent effects of oxygen on atomic structure and mechanical properties of metallic glasses.

Although minor alloying in metallic glasses (MGs) has been extensively investigated, the effect of O doping is still a debatable topic. In the present study, the atomic-level structures and mechanical properties of Zr-based MGs doped with different O contents have been analyzed using ab initio molecular dynamics simulations. It is revealed that O atoms prefer to bond to Zr atoms due to their low mixing enthalpy, and that O atoms degrade the properties of Zr-lean MGs but hardly affect the properties of Zr-rich MGs, with results suggesting a compositional dependence of O doping. For Zr-lean MGs, the fraction of full icosahedra, size of the medium-range-order clusters, Young's modulus and shear modulus decrease sharply with O content, while accompanied by a sharp increase of the non-Frank-Kasper polyhedra, and the ratio of bulk modulus to shear modulus and Poisson's ratio, indicating decreased strength and improved plasticity. For Zr-rich MGs, however, the above-mentioned structural and mechanical features experience little change or only change slightly after O doping, showing low oxygen sensitivity. It is shown that the high Zr content weakens the effect of Zr-O bonding to some extent. The present study not only sheds light on the atomic-level structures of O-doped MGs, which may provide guidelines for designing MGs with low-grade materials, but also helps to explain the previous conflicting results based on the composition-dependence effect.

[Integrated management and prognosis analysis of fetus with complete transposition of the great arteries during pregnancy and perinatal period].

Objective: To investigate the prenatal diagnosis, integrated management and prognosis of fetal complete transposition of the great arteries (D-TGA) detected by ultrasonography. Methods: The prenatal diagnosis, integrated management and prognosis of 19 D-TGA fetuses found by ultrasound during pregnancy in Peking University People's Hospital from January 2014 to June 2019 were analyzed retrospectively. Results: The incidence of D-TGA was 0.12% (19/16 028) among fetuses diagnosed by ultrasound during 5 years. Among the 19 cases, there were 7 cases (7/19) of D-TGA alone, 7 cases (7/19) of D-TGA combined with ventricular septal defect (VSD), 5 cases (5/19) of D-TGA combined with other cardiac malformations; 2 cases (2/19) of D-TGA combined with extra cardiac malformations, and 1 case (1/19) of fetal growth restriction. Nuchal translucency (NT) thickening was found in 3 cases (3/19) at the first trimester of pregnancy. Among the 19 D-TGA fetuses found by ultrasound examination, 18 (18/19) had chromosome karyotype analysis of fetuses or newborns, and chromosomal abnormalities were found in 2 cases, all of which were terminated in the second trimester of pregnancy. The integrated management and multidisciplinary diagnosis and treatment of D-TGA fetuses during pregnancy and perinatal period were carried out. Nine cases (9/19) had induction in the second trimester of pregnancy, 10 cases (10/19) were delivered at term, and the gestational week of delivery was (38.3±0.7) weeks, among which 6 cases (6/10) were delivered by caesarean section due to obstetric factors, and 4 cases (4/10) were delivered by vaginal birth. The oxygen saturation was (69.2±11.3)% at birth and (77.8±6.7)% when transferred to the department of pediatrics. Except for one case lost to follow-up, the other 9 newborns received operation. The average operation time was (21.8±22.1) days after birth, 8 cases (8/9) completed one operation and 1 case (1/9) performed two operations. All of the 9 cases treated by surgery were followed up well. Conclusions: Prenatal diagnosis, individualized evaluation and integrated management during pregnancy and perinatal period should be carried out for the patients with fetal D-TGA detected by ultrasound. Fetal D-TGA is not an indication of cesarean section. The open of ductus arteriosus can be maintained with drugs when necessary after birth, and a good prognosis could be obtained through surgery.

[Characteristics and prognosis of interrupted inferior vena cava with azygous continuation].

Objective: To explore the clinical characteristics of interrupted of the inferior vena cava with azygous continuation and the prognosis. Methods: Retrospective analysis of 21 fetuses diagnosed with interrupted inferior vena cava with azygous continuation among 28 567 pregnant women who underwent routine ultrasound scan. The clinical data, ultrasonographic features, genetic information and prognosis were collected. Results: Interrupted of the inferior vena cava with azygous continuation occurred in 21(0.07%, 21/28 567) of 28 567 patients. Three fetuses (14%, 3/21) complicated with heart and extracardiac malformations, including endocardiac cushion defect, single atrium and single ventricle, double superior vena cava, dextrocardia, asplenia syndrome, visceral heterotaxy, duodenal atresia; six fetuses (29%, 6/21) were associated with cardiac anomalies, such as hypoplastic left heart syndrome, double outlet right ventricle, pulmonary stenosis, ventricular septal defect, persistent left superior vena cava, endocardiac cushion defect and transposition of the great arteries; six cases (29%, 6/21) were only combined with extracardiac malformations, includingasplenia syndrome, visceral heterotaxy, duodenal atresia. Three fetuses (14%, 3/21) were nonorganic abnormalities included thickening of the right ventricle wall, fetal bradycardia, pericardial effusion, hydrops abdominis, increased peak systolic velocity/end diastolic velocity and single umbilical artery. Three fetuses (14%, 3/21) were isolated interrupted inferior vena cava with azygous continuation, but without other anomalies and 2 of them had normal fetal karyotype. Five cases (24%, 5/21) were successfully vaginal delivery, 1 case (5%, 1/21) had cesarean section. After 12-40 months follow-up, we didn't obeserve obviously abnormality, nor any chromosomal abnormality. Ten patients (48%, 10/21) opted for termination of the pregnancy and the autopsies were not done. Five cases (24%, 5/21) were lost to follow up. Conclusions: Interrupted inferior vena cava with azygous continuation are associated with cardiovascular and extracardiac anomalies, cardiac malformation and visceral heterotaxy are the most common anomalies. Visceral heterotaxy should be considered and fetal karyotype should be suggested. In the cases of isolated interrupted inferior vena cava with azygous continuation and normal karyotype, the outcome is favorable.

Cinnamon effectively inhibits the activity of leukemia stem cells.

Cinnamon is the main component of Sanyangxuedai, which is one of the effective traditional Chinese medicines for treating malignancies. Leukemia is a prevalent malignant disease that Sanyangxuedai has been used to treat. Although successful in several studies, there is a lack of solid evidence as to why Sanyangxuedai has an effect on leukemia, and little is known about the underlying mechanisms. In this study, the active ingredients of cinnamon were isolated, purified, and identified. The transwell transport pool formed with the Caco-2 cell model was used to filter the active ingredients of cinnamon by simulating the gastrointestinal barrier in vitro. Moreover, the cell morphology, cell cycle status, apoptosis status, and antigenic variation of the cell surface antigens were observed and measured in K562 cells after treatment with the active ingredients of cinnamon. Our results showed that 50-75 µM was a safe concentration of cinnamon extract for treatment of K562 cells for 72 h. The cinnamon extract caused growth inhibition of K562 cells. Cinnamon extract seemed to arrest the cells at the G1 stage and increased the apoptosis rate significantly. Interestingly, cinnamon extract treatment upregulated the expression of erythroid and myeloid differentiation antigens and downregulated that of the megakaryocytic differentiation antigens in a dose-dependent manner. Our findings indicate that cinnamon extract from Sanyangxuedai may be effective for treating leukemia.

Molecular dynamics simulations on the frictional behavior of a perfluoropolyether film sandwiched between diamond-like-carbon coatings.

We perform molecular dynamics simulations to investigate the nanoscale frictional behavior of a perfluoropolyether (PFPE) film sandwiched between two diamond-like-carbon (DLC) coatings. We show that the PFPE films behave like a solid and can perform either a motion-station movement or a continuous motion with fluctuating velocities. The former movement is caused by the alternating stick and slip at the two individual interfaces, while the latter is due to the dynamic sliding motions simultaneously occurring at both interfaces. We reveal that these motion characteristics are governed by the competition between the two interfacial adhesion energies, which are strongly affected by the thermal vibrations and interface roughness fluctuations. We also find that the Amonton's law modified by incorporating the adhesion effect can be used to describe the mean friction traction vs normal pressure relation, but large fluctuations are present at low contact pressures. The magnitude of atomic level friction forces at the interface is found to be highly nonuniform. The directions of atomic level friction forces can even be opposite. With increasing the normal pressure, the nonuniformity of atomic level friction forces decreases first and then increases again. This change can be explained by the concurrent effects from the large difference in material stiffness and the changes in surface roughness under normal pressure. The present work reveals interesting insights into the sliding mechanisms in sandwiched structures and provides useful guidelines for the design of nanoscale lubricant systems.

Serum lipid abnormalities are not associated with apoB 3' VNTR polymorphism in nephrotic children.

Apolipoprotein B (apoB) gene 3' variable number of tandem repeat (VNTR) is highly variable, and therefore can be an informative marker for associative analysis of lipid metabolism. This is the first report focusing on a possible association of apoB VNTR polymorphism with nephrotic hyperlipidemia. Genomic DNA was extracted from 500 children with primary nephrotic syndrome (PNS) and 500 healthy controls. The apoB genotype was determined by PCR analysis. Allele size distribution followed a unimodal curve, with the main peak at the hypervariable element 35 (HVE35); the most prevalent genotype was HVE35/35 in both control and PNS children. The genotype and allele distributions of apoB variants in PNS children were not significantly different from controls. There was significant variation in serum lipid profiles among different genotypes in control children. Individuals with the long (L) allele exhibited significantly higher total cholesterol, low-density lipoprotein cholesterol (LDL-C) and apoB levels than those with the medium (M) or short (S) allele; consequently, M/L carriers had significantly higher total cholesterol, LDL-C and apoB concentrations than did S/S, S/M, S/L, or M/M carriers. However, in PNS children, no significant differences in serum lipid levels were observed among individuals with different genotypes and alleles of apoB 3' VNTR. We conclude that hyperlipidemia in nephrotic children is not associated with apoB 3' VNTR polymorphism.

Atomistic-scale analysis of the deformation and failure of polypropylene composites reinforced by functionalized silica nanoparticles.

Interfacial adhesion between polymer matrix and reinforcing silica nanoparticles plays an important role in strengthening polypropylene (PP) composite. To improve the adhesion strength, the surface of silica nanoparticles can be modified by grafted functional molecules. Using atomistic simulations, we examined the effect of functionalization of silica nanoparticles by hexamethyldisilazane (HMDS) and octyltriethoxysilane (OTES) molecules on the deformation and failure of silica-reinforced PP composite. We found that the ultimate tensile strength (UTS) of PP composite functionalized by OTES (28 MPa) is higher than that of HMDS (25 MPa), which is in turn higher than that passivated only by hydrogen (22 MPa). To understand the underlying mechanistic origin, we calculated the adhesive energy and interfacial strength of the interphase region, and found that both the adhesive energy and interfacial strength are the highest for the silica nanoparticles functionalized by OTES molecules, while both are the lowest by hydrogen. The ultimate failure of the polymer composite is initiated by the cavitation in the interphase region with the lowest mass density, and this cavitation failure mode is common for all the examined PP composites, but the cavitation position is dependent on the tail length of the functional molecules. The present work provides interesting insights into the deformation and cavitation failure mechanisms of the silica-reinforced PP composites, and the findings can be used as useful guidelines in selecting chemical agents for surface treatment of silica nanoparticles.

Polymer light-emitting electrochemical cells.

A device configuration for light emission from electroactive polymers is described. In these light-emitting electrochemical cells, a p-n junction diode is created in situ through simultaneous p-type and n-type electrochemical doping on opposite sides of a thin film of conjugated polymer that contains added electrolyte to provide the necessary counterions for doping. Light-emitting devices based on conjugated polymers have been fabricated that operate by the proposed electrochemical oxidation-reduction mechanism. Blue, green, and orange emission have been obtained with turn-on voltages close to the band gap of the emissive material.

Long noncoding RNA SNHG14 accelerates cell proliferation, migration, invasion and suppresses apoptosis in colorectal cancer cells by targeting miR-944/KRAS axis through PI3K/AKT pathway.

OBJECTIVE: Colorectal cancer (CRC) is a gastrointestinal tract cancer, which threatens the well-being of million of patients due to high metastasis. Recently, numerous studies have recognized nuclear RNA host gene 14 (SNHG14) as a remarkable oncogene in different cancers. However, the regulatory mechanism of SNHG14 in CRC development is mostly unclear. PATIENTS AND METHODS: The expression of SNHG14, miR-944 and Kirsten rat sarcoma (KRAS) in tissues and cells was measured by quantitative Real-time polymerase chain reaction (qRT-PCR). Cell viability and apoptosis were evaluated by cell counting kit-8 (CCK-8) and flow cytometry assay, respectively. Cell migration and invasion were assessed using transwell assay. Protein expression of KRAS, AKT, phosphorylated AKT (p-AKT), phosphatidylinositol-3-kinase (PI3K) and phosphorylated PI3K (p-PI3K) was detected by Western blot. Animal models were constructed by subcutaneously injecting SW620 cells stably transfected with sh-SNHG14 and sh-NC. The interaction among SNHG14, miR-944 and KRAS was determined by luciferase reporter assay and RIP assay. RESULTS: The expression of SNHG14 and KRAS was up-regulated whereas miR-944 was down-regulated in CRC tumors and cells compared with normal tissues and cells. In addition, SNHG14 silencing attenuated cell proliferation, migration and invasion, while accelerated apoptosis in CRC cells by suppressing PI3K/AKT pathway. Consistently, SNHG14 knockdown hindered tumor growth in vivo. MiR-944 was a target of SNHG14 and directly targeted KRAS. Moreover, miR-944 inhibitor abrogated silenced SNHG14-mediated inhibition on proliferation, migration and invasion, as well as promotion on apoptosis in CRC cells. Similarly, miR-944 regulated CRC cell progression by targeting KRAS through PI3K/AKT pathway. CONCLUSIONS: SNHG14 contributed to cell proliferation, migration and invasion, while suppressed apoptosis in CRC cells by targeting miR-944/KRAS axis through PI3K/AKT pathway, representing novel biomarkers for CRC therapy.

Molecular dynamics study on DNA oligonucleotide translocation through carbon nanotubes.

Molecular dynamics simulations are performed to study the translocation of a DNA oligonucleotide in a carbon nanotube (CNT) channel consisting of CNTs of two different diameters. A strong gravitational acceleration field is applied to the DNA molecule and water solvent as an external driving force for the translocation. It is observed that both the CNT channel size and the strength of gravitational field have significant influence on the DNA translocation process. It is found that the DNA oligonucleotide is unable to pass through the (8,8) CNT even under strong gravitational fields, which extends previous finding that DNA cannot be self-inserted into a (8,8) CNT. It is shown that the DNA can pass through the (10,10)-(12,12) and (12,12)-(14,14) CNTs with stronger gravitational field resulting in faster translocation. The translocation time tau is found to follow the inverse power law relationship with the gravitational acceleration a as tau approximately a(-1.21). The energetic analysis of the translocation process shows that there is an energy barrier for DNA translocation into the (10,10) tube from the (14,14) tube, which is in contrast to previous report that DNA can be self-inserted into a (10,10) tube from outside the CNT. This difference with previous report shows that the dynamic behavior of DNA translocation inside a CNT channel is quite different from that of DNA translocation into a CNT from outside the CNT.

[Clinical characteristics of 6 patients with blastic plasmacytoid dendritic cell neoplasm].

Objective: To explore the clinical characteristics, treatment, and prognosis of patients with blastic plasmacytoid dendritic cell neoplasm. Method: Clinical records of 6 patients diagnosed with blastic plasmacytoid dendritic cell neoplasm in our hospital from January 2008 to May 2016 were collected and retrospectively analyzed. Results: Six patients manifested with initial symptoms of skin lesions, other common symptoms included bone marrow involvement (5/6) , lymphadenectasis (4/6) , splenomegaly (4/6) , and hepatomegaly (3/6) . In addition, extra-nodal involvement except skin was also observed, including breast (1/6) , maxillary sinus (1/6) , vertebrae (1/6) , and central nervous system (1/6) . Characteristic immunophenotype, CD4, CD56, and CD123 were all positive. All these patients were treated with acute lymphoblastic leukemia type (ALL-type) chemotherapy and complete remission (CR) were reached in 4 patients. The median follow-up was 9.5 (7-37) months, median progression free survival was 7 months; while median overall survival was 9 months. A total of 3 patients died during the follow-up, which were all happened in the first year after diagnosis, and all resulted from the relapse or disease progression. Conclusion: Blastic plasmacytoid dendritic cell neoplasm is highly aggressive, in which the skin lesions are always manifested as initial symptoms, and bone marrow involvement, lymphadenectasis, splenomegaly, and hepatomegaly is also common. Characteristic immunophenotype include the positivity of CD4, CD56, and CD123. Effective and standard therapy is limited in this disease, which indicates the poor prognosis.

Automated Robotic Dispensing Technique for Surface Guidance and Bioprinting of Cells.

This manuscript describes the introduction of cell guidance features followed by the direct delivery of cells to these features in a hydrogel bioink using an automated robotic dispensing system. The particular bioink was selected as it allows cells to sediment towards and sense the features. The dispensing system bioprints viable cells in hydrogel bioinks using a backpressure assisted print head. However, by replacing the print head with a sharpened stylus or scalpel, the dispensing system can also be employed to create topographical cues through surface etching. The stylus movement can be programmed in steps of 10 µm in the X, Y and Z directions. The patterned grooves were able to orientate mesenchymal stem cells, influencing them to adopt an elongated morphology in alignment with the grooves' direction. The patterning could be designed using plotting software in straight lines, concentric circles, and sinusoidal waves. In a subsequent procedure, fibroblasts and mesenchymal stem cells were suspended in a 2% gelatin bioink, for bioprinting in a backpressure driven extrusion printhead. The cell bearing bioink was then printed using the same programmed coordinates used for the etching. The bioprinted cells were able to sense and react to the etched features as demonstrated by their elongated orientation along the direction of the etched grooves.

Low expression of long non-coding RNA-LET can indicate metastasis and a poor prognosis: a meta-analysis.

BACKGROUND: Recent studies have reported that the lncRNA-LET was down-regulated in several cancers.The current meta-analysis aims to determine whether lncRNA-LET can be used as a potential biomarker for metastasis and prognosis. METHODS: We collected all relevant papers by searching multiple electronic databases(Pubmed,EMBASE,Google Scholar,CNKI,Wanfang database) and explored the association between the expression levels of lncRNA-LETand lymph node metastasis (LNM),distant metastasis (DM) and overall survival (OS). RESULTS: A total of 383 patients from four studies were finally included.The meta-analysis results showed that LNM occurred more frequently in patients with low lncRNA-LET expression group than in patients with high lncRNA-LET expression group(OR=4.56,95%CI:2.92-7.12,p<0.00001),and a similar result was observed between lncRNA-LET expression and DM,the OR was 4.77(95%CI:2.29-9.94, p<0.0001).Additionally,we found that patient with low lncRNA-LET expression had a poorer OS than those high lncRNA-LET expression (HR=2.39,95 %CI:1.57-3.21,p = 0.000). CONCLUSION: LncRNA-LETmay serve as a common molecular marker for metastasis and prognosis in human cancers.

The association of HOTAIR expression with clinicopathological features and prognosis in gastric cancer patients.

INTRODUCTION: A number of studies in gastric carcinoma have demonstrated that cancerous tissues have a significant higher HOTAIR level than that in noncancerous tissues. Overexpression of HOTAIR is associated with the development in gastric cancer. EVIDENCE ACQUISITION: We collected all relevant articles and explored the association of HOTAIR expression with clinicopathological features and prognosis in patients with gastric cancer. Literature collections were conducted by searching a number of electronic databases (up to November 15, 2015). The meta-analysis was conducted by using RevMan v.5.3 software and Stata SE 12.0. EVIDENCE SYNTHESIS: A total of 832 patients with gastric cancer based on 10 studies were included. The Meta-analysis results showed that high-expression of HOTAIR is significantly associated with clinicopathological features in gastric cancer patients, especially in the depth of tumor invasion, lymph node metastasis, vessel invasion, lymphatic vessel involvement and TNM stage, but there is no association between HOTAIR overexpression and other clinicopathological features. In addition, aberrant HOTAIR expression is also significantly associated with the prognosis in gastric cancer patients. CONCLUSIONS: There is an association between HOTAIR expression and clinicopathological features and prognosis in gastric cancer patients. High expression of HOTAIR in cancerous tissue could predict poor clinical outcome in gastric cancer, suggesting HOTAIR abundance may serve as a novel candidate biomarker for the clinical outcome in gastric cancers.

Long noncoding RNA PVT1, a novel promising biomarker to predict lymph node metastasis and prognosis: a meta-analysis.

BACKGROUND: Numerous studies have found that the expression levels of long noncoding RNA PVT1 (lncRNA PVT1) were elevated in cancerous tissue, which was significantly higher than those in adjacent noncancerous tissues or corresponding normal tissues. Overexpression of lncRNA PVT1 was correlated with lymph node metastasis and a poor prognosis in various cancers. METHODS: This quantitative meta-analysis collected all relevant articles and explored the association of lncRNA PVT1 expression levels with lymph node metastasis and prognosis. The systematic search was conducted through multiple electronic databases (up to December 1, 2015). The meta-analysis was performed by using RevMan5.3 software and Stata SE12.0. RESULTS: A total of 939 patients with cancer from 10 studies were included. The Meta-analysis results showed that cancer patients with high PVT1 have a strong trend for LNM (OR=2.05, 95%CI:0.97-4.30, P=0.06, random-effects model). Moreover, we found that cancer patients with high PVT1 expression had a poorer overall survival (HR=2.07, 95%CI:1.40-2.74, P=0.000, fixed-effects model), a shorter recurrence-free survival (HR=1.70, 95%CI:1.02-2.39, P=0.000, fixed-effects model), and a worse disease-free survival (HR:2.10, 95%CI:0.96-3.23, P=0.000, fixed-effects model). CONCLUSIONS: PVT-1 may serve as a novel molecular marker for lymph node metastasis and prognosis.

Effects of genetic factors on the pharmacokinetics and pharmacodynamics of amlodipine in primary hypertensive patients.

The aim of the present study was to explore the effects of common genetic polymorphisms of cytochrome P450 (CYP)3A4, CYP3A5, cytochrome P450 oxidoreductase (POR) and multidrug resistance protein 1 (MDR1) on the pharmacokinetics and pharmacodynamics of amlodipine in primary hypertensive patients. The mild-to-moderate essential hypertension patients were recruited to complete the genotyping of CYP3A4, CYP3A5, POR and MDR1 by sequencing. After a 1-week placebo washout period, the subjects received 5 mg oral amlodipine daily for 4 weeks. Serial blood samples were collected prior to the last dosing, and 2, 6 and 24 h post-dosing. Blood pressures were measured prior and subsequent to dosing, and the demographical data were also collected. The blood samples were collected for laboratory testing. The plasma concentrations of amlodipine were determined by high-performance liquid chromatography/tandem mass spectrometry. A total of 60 patients, including 31 males and 29 females, completed the 4-week treatment. The plasma concentration of amlodipine in females at each time point was significantly higher compared to males (P<0.05). However, no significant gender differences existed in antihypertensive efficacy. The genetic polymorphisms of MDR1 C3435T had a certain impact on the plasma concentration of amlodipine, but did not affect its antihypertensive efficacy (P>0.05). The genetic polymorphisms of CYP3A4*1G, CYP3A5*3 and POR A503V showed no impact on plasma concentration and efficacy of amlodipine (P>0.05). Gender and MDR1 gene polymorphism may affect the plasma concentration of amlodipine in hypertensive patients. However, there was no impact on the efficacy of amlodipine.

Necking and notch strengthening in metallic glass with symmetric sharp-and-deep notches.

Notched metallic glasses (MGs) have received much attention recently due to their intriguing mechanical properties compared to their unnotched counterparts, but so far no fundamental understanding of the correlation between failure behavior and notch depth/sharpness exists. Using molecular dynamics simulations, we report necking and large notch strengthening in MGs with symmetric sharp-and-deep notches. Our work reveals that the failure mode and strength of notched MGs are strongly dependent on the notch depth and notch sharpness. By increasing the notch depth and the notch sharpness, we observe a failure mode transition from shear banding to necking, and also a large notch strengthening. This necking is found to be caused by the combined effects of large stress gradient at the notch roots and the impingement and subsequent arrest of shear bands emanating from the notch roots. The present study not only shows the failure mode transition and the large notch strengthening in notched MGs, but also provides significant insights into the deformation and failure mechanisms of notched MGs that may offer new strategies for the design and engineering of MGs.