Self-Assembly of Wireframe DNA Nanostructures from Junction Motifs

Wireframe frameworks have been investigated for the construction of complex nanostructures from a scaffolded DNA origami approach; however, a similar framework is yet to be fully explored in a scaffold-free "LEGO" approach. Herein, we describe a general design scheme to construct wireframe DNA nanostructures entirely from short synthetic strands. A typical edge of the resulting structures in this study is composed of two parallel duplexes with crossovers on both ends, and three, four, or five edges radiate out from a certain vertex. By using such a self-assembly scheme, we produced planar lattices and polyhedral objects.

Ultrasonic modulation of phase separation and corrosion resistance for ternary Cu-Sn-Bi immiscible alloy

The effect of power ultrasound on the liquid phase separation of ternary Cu-32%Sn-20%Bi immiscible alloy is experimentally investigated, which shows that as compared with the layered structure formed under static condition, the macrosegregation resulted from liquid phase separation is remarkably reduced with the increase of ultrasonic amplitude. A homogenous microstructure characterized by refined (Bi) particles dispersing uniformly on the (Cu₃Sn) matrix is obtained when the ultrasonic amplitude reaches the highest value of 24 μm. This is mainly ascribed to the ultrasonically induced cavitation and acoustic streaming, which promotes the nucleation, the fragmentation, and the dispersion of (Bi) droplets. The finally solidified immiscible alloy exhibits obvious improvements in electrochemical corrosion resistance, microhardness and wear-resisting if compared with those in static solidification. These results prove that applying power ultrasound is an effective way to modulate the liquid phase separation and enhance the applied performance for immiscible alloys.

Proton migration in hydrocarbons induced by slow highly charged ion impact

Different from most of the previous studies using light or photons, we use highly charged ions as projectiles to activate proton migration in the smallest saturated and unsaturated hydrocarbon molecules, i.e., CH₄ and C₂H₂. The H₃ ⁺ formation channel (H₃ ⁺ + CH⁺) and isomerization channel (C⁺ + CH₂ ⁺), serving as indicators of proton migration, are observed in the fragmentation of CH₄ and C₂H₂ dications. Corresponding kinematical information, i.e., kinetic energy release, is for the first time obtained in the collisions with highly charged ions. In particular, for the C⁺ + CH₂ ⁺ channel, a new pathway is identified, which is tentatively attributed to the isomerization on high-lying states of acetylene dication. The kinetic energy release spectra for other two-body breakup channels are also determined and precursor dication states could thus be identified.

Correction: Transport mechanisms in a puckered graphene-on-lattice

Correction for 'Transport mechanisms in a puckered graphene-on-lattice' by T. Xu et al., Nanoscale, 2018, 10, 7519-7525.

A theoretical study of Ar8+-acetylene collisions at 1.2 MeV: Ionization and dissociation dynamics

We theoretically study Ar⁸⁺-induced dissociation of C₂H₂ molecule at 1.2 MeV using the time-dependent density-functional theory non-adiabatically coupled to nuclear dynamics. We find that molecular dissociation depends strongly on the ionization at the initial stage and the collision configuration. A detailed analysis shows a correspondence between the charge state of [C₂H₂]^q+ and the final fragments. A remarkable impact parameter effect provides deep insights of bond breakup and electronic transport. We analyze two typical sequential dissociation channels reported in experiments by tracking structural and electronic dynamics in real time. Our results provide better understanding of experiments. Moreover, the comparison between various exchange-correlation functionals reveals that electrons' correlation and self-interaction do not significantly impact the initial ionization and fragment distribution in the present study.

Multivariate analysis of inflammatory endotypes in recurrent nasal polyposis in a Chinese population

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) remains a challenging clinical problem due to its propensity for recurrence. However, data on the frequency of CRSwNP recurrence after surgery in China are rare.

METHODS

78 CRSwNP patients undergoing functional endoscopic sinus surgery were followed-up for 8 years and classified into recurrent and non-recurrent groups. A cluster analysis of the CRSwNP based on inflammatory endotypes was performed, and the endotypes were secondarily matched with clinical phenotypes.

RESULTS

The recurrence rate of CRSwNP in Southwest China was 21.8% over 8 years post-surgery. The CRSwNP was classified into 4 clusters: cluster 1 (higher expression of IL-5, IgE, and ECP and high positivity rate for SE-IgE); cluster 2 (higher concentrations of IL-6, IL-8 and MPO); cluster 3 (higher concentrations of TNF-alpha; and IFN-gamma); and cluster 4 (higher expression of IL-17). Cluster 1 (type-2 inflammation) exhibited the highest recurrence rate, co-morbid asthma and atopy. Notably, the ECP/MPO ratio increased significantly in patients with non-type-2 recurrent CRSwNP 8 years after the first surgery.

CONCLUSION

Different inflammatory endotypes of CRSwNP exhibited clearly different prognoses. The type-2 subgroup had high recurrence and co-morbid asthma rates comparable to the rates reported in Western countries.

Hierarchical Assembly of DNA Nanostructures Based on Four-Way Toehold-Mediated Strand Displacement

Because of its attractive cost and yield, hierarchical assembly, in which constituent structures of lower hierarchy share a majority of components, is an appealing approach to scale up DNA self-assembly. A few strategies have already been investigated to combine preformed DNA nanostructures. In this study, we present a new hierarchical assembly method based on four-way toehold-mediated strand displacement to facilitate the combination of preformed DNA structural units. Employing such a method, we have constructed a series of higher-order structures composed of 5, 7, 9, 11, 13, and 15 preformed units respectively.

Local Schottky contacts of embedded Ag nanoparticles in Al2O3/SiN x :H stacks on Si: a design to enhance field effect passivation of Si junctions

This paper describes an original design leading to the field effect passivation of Si n⁺-p junctions. Ordered Ag nanoparticle (Ag-NP) arrays with optimal size and coverage fabricated by means of nanosphere lithography and thermal evaporation, were embedded in ultrathin-Al₂O₃/SiN _x :H stacks on the top of implanted Si n⁺-p junctions, to achieve effective surface passivation. One way to characterize surface passivation is to use photocurrent, sensitive to recombination centers. We evidenced an improvement of photocurrent by a factor of 5 with the presence of Ag NPs. Finite-difference time-domain (FDTD) simulations combining with semi-quantitative calculations demonstrated that such gain was mainly due to the enhanced field effect passivation through the depleted region associated with the Ag-NPs/Si Schottky contacts.

Transport mechanisms in a puckered graphene-on-lattice

Understanding the fundamental properties of graphene when its topography is patterned by the use of a compliant substrate is essential to improve the performances of graphene sensors. Here we suspend a graphene monolayer on SiO2 nanopillar arrays to form a puckered graphene-on-lattice and investigate the strain and electrical transport at the nanoscale. Despite a nonuniform strain in the graphene-on-lattice, the resistivity is governed by thermally activated transport and not the strain. We show that the high thermal activation energy results from a low charge carrier density and a periodic change of the chemical potential induced by the interaction of the graphene monolayer with the nanopillars, making the use of graphene-on-lattice attractive to further increase the electrical response of graphene sensors.

Systematic review with meta-analysis: effectiveness and tolerability of interferon-free direct-acting antiviral regimens for chronic hepatitis C genotype 1 in routine clinical practice in Asia

BACKGROUND

Direct-acting antiviral (DAA) regimens have shown high efficacy and tolerability for patients with HCV genotype 1/1b (GT1/1b) in clinical trials. However, robust real-world evidence of interferon (IFN)-free DAA treatment for HCV GT1-infected patients in Asia is still lacking.

AIM

To systematically review and meta-analyse the effectiveness and tolerability of IFN-free DAA therapy for HCV GT1 infection in Asia.

METHODS

We included studies that enrolled adult patients with HCV GT1 infection in routine clinical practice in Asia, using IFN-free DAA regimens, and reported sustained virological response (SVR) after 12/24 weeks end-of-treatment by 31 May 2017. The pooled SVR rates were computed with a random-effects model. Subgroup analysis and meta-regression as previously registered in PROSPERO were performed to determine how pre-planned variables might have affected the pooled estimates.

RESULTS

We included 41 studies from eight countries and regions, comprising of 8574 individuals. The pooled SVR rates for GT1 were 89.9% (95% CI 88.6-91.1, I²  = 55.1%) with daclatasvir/asunaprevir (DCV/ASV) and 98.1% (95% CI 97.0-99.0, I²  = 41.0%) with ledipasvir/sofosbuvir ± ribavirin (LDV/SOF ± RBV). Baseline cirrhosis but not prior treatment history and age, attenuated the effectiveness of both regimens. Baseline resistance associated substitutions (RASs) severely attenuated SVR of DCV/ASV (65.4% vs 94.3%, P < 0.001) and only minimally with LDV/SOF ± RBV (94.5% vs 99.2%, P = 0.003). Patients with renal dysfunction treated with DCV/ASV showed a higher SVR rate (93.9% vs 89.8%, P = 0.046). Patients with hepatocellular carcinoma (HCC) LDV/SOF ± RBV achieved a lower SVR than those without HCC (94.1% vs 98.7%, P = 0.001).

CONCLUSION

All oral DAA treatment of HCV GT1 resulted in high cure rates in Asian patients in routine clinical practice setting including elderly patients and those with end-stage renal disease.

[The role and significance of digital reconstruction technique in liver segments based on portal vein structure]

Objective: To study the segment of liver according to the large amount of three-dimensional(3D) reconstructive images of normal human livers and the vascular system, and to recognize the basic functional liver unit based on the anatomic features of the intrahepatic portal veins. Methods: The enhanced CT primitive DICOM files of 1 260 normal human livers from different age groups who treated from October 2013 to February 2017 provided by 16 hospitals were analyzed using the computer-aided surgery system.The 3D liver and liver vascular system were reconstructed, and the digital liver 3D model was established.The vascular morphology, anatomical features, and anatomical distributions of intrahepatic portal veins were statistically analyzed. Results: The digital liver model obtained from the 3D reconstruction of CAS displayed clear intrahepatic portal vein vessels of level four.Perform a digital liver segments study based on the analysis of level four vascular distribution areas.As the less anatomical variation of left hepatic portal vein, the liver was classified into four types of liver segmentation mainly based on right hepatic portal vein.Type A was similar to Couinaud or Cho's segmentation, containing 8 segments(537 cases, 42.62%). Type B contained 9 segments as there are three ramifications of right-anterior portal vein(464 cases, 36.82%). The main difference for Type C was the variation of right-posterior portal vein which was sector shape(102 cases, 8.10%). Type D contained the cases with special portal vein variations, which needs three-dimensional simulation to design individualized liver resection plan(157 cases, 12.46%). These results showed that there was no significant difference in liver segmental typing between genders(χ(2)=2.179, P=0.536) and did not reveal any significant difference in liver segmental typing among the different age groups(χ(2)=0.357, P=0.949). Conclusions: The 3D digital liver model can demonstrate the true 3D anatomical structures, and its spatial vascular variations.The observation of anatomic features, distribution areas of intrahepatic portal veins and individualized liver segmentation achieved via digital medical 3D visualization technology is of great value for understand the complexity of liver anatomy and to guide the precise hepatectomy.

[Effect of different anesthetic methods on postoperative outcomes in elderly patients undergoing hip fracture surgery]

OBJECTIVE

To investigate the effect of general or regional anesthesia on postoperative cardiopulmonary complications and inpatient mortality after hip fracture surgery in elderly patients.

METHODS

A retrospective analysis was conducted according to the medical records of 572 elderly patients with hip fractures admitted to our hospital from January 1, 2005 to December 31, 2014. The age, gender, preoperative comorbidities, length of preoperative bedridden time, mechanism of injury, surgical types, anesthetic methods, major postoperative complications and inpatient mortality were recorded. Multivariate Logistic regression analysis was applied to analyze the impact of different anesthetic methods on inpatient mortality in these patients.

RESULTS

Of the 572 patients, 392 (68.5%) received regional anesthesia. Inpatient death occurred in 8 (8/572, mortality: 1.4%), including 5 cases of RA group (5/392, mortality: 1.3%) and 3 cases of GA group (3/180, mortality: 1.7%). There was no statistically significant difference between the two groups in inpatient mortality (P>0.05). Multiple Logistic regression analysis showed that gender (odds ratio: 0.18, 95% CI: 0.03-1.05, P=0.057), age (odds ratio: 1.22, 95% CI: 1.07-1.38, P=0.002), preoperative pulmonary comorbidities (odds ratio: 12.09, 95% CI: 2.28-64.12, P=0.003) and surgical types (odds ratio: 9.36, 95% CI: 1.34-64.26, P=0.024) were risk factors for inpatient mortality. Postoperative cardiovascular complications occurred in 36 patients (36/572, morbidity: 6.3%), with 19 patients in RA group (19/392, morbidity: 4.8%),and 17 patients in GA group (17/180, morbidity: 9.4%). Multiple Logistic regression analysis showed that age (odds ratio: 1.13, 95% CI: 1.07-1.19, P<0.001), hypertension (odds ratio: 2.72, 95% CI: 1.24-5.96, P=0.012) and preoperative cerebral comorbidities (odds ratio: 2.11, 95% CI: 0.99-4.52, P=0.054) were risk factors for postoperative cardiovascular complications. Postoperative pulmonary complications occurred in 56 patients (56/572, morbidity: 9.8%), with 19 patients in RA group (19/392, morbidity: 4.8%), and 37 patients in GA group (37/180, morbidity: 20.6%). Multiple Logistic regression analysis showed that age (odds ratio: 1.13, 95% CI: 1.07-1.19, P<0.001), preoperative pulmonary comorbidities (odds ratio: 2.89, 95% CI: 1.28-7.05, P=0.020), length of preoperative bedridden time (odds ratio: 1.11, 95% CI: 1.04-1.18, P=0.003) and anesthetic methods (odds ratio: 5.86, 95% CI: 2.98-11.53, P<0.001) were risk factors for postoperative pulmonary complications.

CONCLUSION

General anesthesia may not affect the inpatient mortality after hip fracture surgery in elderly patients. Regional anesthesia is associated with a lower risk of pulmonary complications after surgical procedure compared with general anesthesia.

Versatile DNA Origami Nanostructures in Simplified and Modular Designing Framework

We introduce a simplified and modular architecture for design and construction of complex origami nanostructures. A series of basic two-dimensional and three-dimensional structures are presented. As the resulting structures can be virtually divided into blocks, modular remodeling such as translocation, contraction/extension, and bending is carried out. Structures under such a designing framework are morphable. Local conformational changes can propagate to the entire structure to reshape the global conformation.

DNA nanostructures constructed with multi-stranded motifs

Earlier studies in DNA self-assembly have foretold the feasibility of building addressable nanostructures with multi-stranded motifs, which is fully validated in this study. In realizing this feasibility in DNA nanotechnology, a diversified set of motifs of modified domain lengths is extended from a classic type. The length of sticky ends can be adjusted to form different dihedral angles between the matching motifs, which corresponds to different connecting patterns. Moreover, the length of rigidity core can also be tuned to result in different dihedral angles between the component helices of a certain motif therefore different numbers of component helices. The extended set of motifs is used for self-assembly of complex one dimensional, two dimensional and three dimensional structures.

[Autophagy regulated by JWA influenced sensitivity of esophageal cancer to cisplatin]

Objective: To explore the effect of JWA on cisplatin sensitivity and its potential molecular mechanism in esophageal cancer. Methods: The siRNA was used to inhibit the JWA expression, then cisplatin sensitivity and LC3 (autophagy related protein) expression levels were observed in TE1 cells.Further, the effect of autophagy inhibitor tamoxifen (3-MA) on above process was determined.Cisplatin sensitivity of 20 fresh esophageal cancer samples was evaluated by histoculture drug response assay (HDRA). Result: Silencing JWA gene increased the sensitivity of TE1 cells to cisplatin (P<0.05), and decreased the LC3-Ⅰ and LC3-Ⅱ proteins induced by cisplatin.Furthermore, combined with 3-MA increased the inhibition rate of cisplatin in JWA silencing group (P<0.05). Additionally, the inhibition rate of cisplatin on tissues with low JWA expression were higher than those with high expression (45.6% vs 25.6%, P=0.005). Conclusions: JWA could influence the cisplatin sensitivity by regulating autophagy in esophageal cancer.

Experimental investigations and phase-field simulations of triple-phase-separation kinetics within liquid ternary Co-Cu-Pb immiscible alloys

The phase-separation kinetics and microstructure evolution mechanisms of liquid ternary Co_{43}Cu_{40}Pb_{17} immiscible alloys are investigated by both the drop tube technique and phase-field method. Two successive phase separations take place during droplet falling and lead to the formation of a three-phase three-layer core-shell structure composed of a Co-rich core, a Cu-rich middle layer, and a Pb-rich shell. The Pb-rich shell becomes more and more conspicuous as droplet diameter decreases. Meanwhile, the Co-rich core center gradually moves away from the core-shell center. Theoretical analyses show that a larger temperature gradient inside a smaller alloy droplet induces the accelerated growth of the surface segregation shell during triple-phase separation. The residual Stokes motion and the asymmetric Marangoni convection result in the appearance of an eccentric Co-rich core and the core deviation degree is closely related to the droplet size and initial velocity. A three-dimensional phase-field model of ternary immiscible alloys, which considers the successive phase separations under the combined effects of Marangoni convection and surface segregation, is proposed to explore the formation mechanisms of three-phase core-shell structures. The simulated core-shell morphologies are consistent with the experimental observations, which verifies the model's validity in reproducing the core-shell dynamic evolution. Numerical results reveal that the development of three-phase three-layer core-shell structures can be attributed to the primary and then secondary phase separations dominated simultaneously by Marangoni convection and surface segregation. Furthermore, the effects of droplet temperature gradient on the growth kinetics of the surface segregation shell are analyzed in the light of phase-field theory.

Sub-100-nm metafluorophores with digitally tunable optical properties self-assembled from DNA

Fluorescence microscopy allows specific target detection down to the level of single molecules and has become an enabling tool in biological research. To transduce the biological information to an imageable signal, we have developed a variety of fluorescent probes, such as organic dyes or fluorescent proteins with different colors. Despite their success, a limitation on constructing small fluorescent probes is the lack of a general framework to achieve precise and programmable control of critical optical properties, such as color and brightness. To address this challenge, we introduce metafluorophores, which are constructed as DNA nanostructure-based fluorescent probes with digitally tunable optical properties. Each metafluorophore is composed of multiple organic fluorophores, organized in a spatially controlled fashion in a compact sub-100-nm architecture using a DNA nanostructure scaffold. Using DNA origami with a size of 90 × 60 nm², substantially smaller than the optical diffraction limit, we constructed small fluorescent probes with digitally tunable brightness, color, and photostability and demonstrated a palette of 124 virtual colors. Using these probes as fluorescent barcodes, we implemented an assay for multiplexed quantification of nucleic acids. Additionally, we demonstrated the triggered in situ self-assembly of fluorescent DNA nanostructures with prescribed brightness upon initial hybridization to a nucleic acid target.

[Enhanced recovery after surgery for the gastrointestinal surgery]

It has already been ten years since the concept of enhanced recovery after surgery (ERAS) was introduced in China. The ERAS protocol focuses on relieving surgical stress and accelerating physiological recovery. From our perspective, besides the post hospital stay, it would be better to evaluate patient's recovery by different indicators. It is important to improve the compliance of ERAS protocol. The guideline-related factors, administration, medical staff and patients have impact on compliance. Integrating stakeholders, strengthening communication and cooperation among multidiscipline teams, combining theory with practice would facilitate use of ERAS protocol in clinical settings.

Answers to if the Lead Aprons are Really Helpful in Nuclear Medicine from the Perspective of Spectroscopy

Wearing lead X-ray-protective aprons is a routine in nuclear medicine department in parts of China. However, the staff are often perplexed by questions such as if it is imperative to wear aprons when injecting radioactive drugs, how much radiation dosage can be shielded and if the apron will produce secondary radiation instead? To answer these questions, a semiconductor detector was employed to record different gamma and X-ray spectra with and without the lead apron or lead sheet. Then, we could estimate the signal shielding ratio to different photons for the lead apron and compare with the hospitals measured data. In general, the two results coincided well. The spectral results showed that the detrimental secondary X-rays irradiation rises when the energy of gamma rays exceeds the K absorption edge of lead (88 keV). Moreover, the aprons are not so effective for gamma rays of 364 keV emitted from 131I and 511 keV emitted from the positron radioactive nuclides. This work is purely a physical measurement in the laboratory. To the best of our knowledge, this is the first quantitative study on the level of gamma rays protection offered by the medical lead aprons and the importance of the spectroscopic measurements is discussed in this paper.

A numerical simulation of acoustic field within liquids subject to three orthogonal ultrasounds

When one beam of ultrasound propagates along a single direction in liquids, the cavitation effect is always confined to a limited volume close to the ultrasonic source. This greatly limits the application of power ultrasound in liquid processing and materials fabrication. In this study, a methodology for applying three orthogonal ultrasounds within liquids has been proposed. By solving the Helmholtz equation, the sound field distribution characteristics are investigated in 1D (one dimensional), 2D (two dimensional) and 3D (three dimensional) ultrasounds at their resonant frequencies, which show that the coherent interaction of three beams of ultrasounds is able to strikingly promote the sound pressure level and reinforce the mean acoustic energy density as compared with that in 1D case. Hence, the potential cavitation volume is enlarged remarkably. This opens new possibilities for the design and optimization of ultrasonic technology in fabricating materials.

Liquid Supercoolability and Synthesis Kinetics of Quinary Refractory High-entropy Alloy

The high-entropy configuration of equiatomic multicomponent alloys opens an effective access to the development of advanced materials. Here we report the synthesis of a new quinary refractory WMoTaNbZr high-entropy alloy under electrostatic levitation condition. It showed a high liquidus temperature of 2686 K and achieved a maximum supercooling of 640 K (0.24 T_L) at molten state. The containerless measurements revealed a linear increasing tendency for both its liquid state density and the specific heat to emissivity ratio versus alloy supercooling. A high-entropy body-centered cubic (HEB) phase dominated its phase constitution despite the formation of a negligible amount of solid solution (Zr) phase. The dendritic growth of HEB phase always governed the crystallization process, attained a fastest growth velocity of 13.5 m/s and displayed a power function relation to alloy supercooling. The high speed videographic research of recalescence phenomenon indicated Johnson-Mehl-Avrami type transition kinetics for its rapid solidification process. As supercooling increases, the microstructures of primary HEB phase were refined conspicuously and exhibited an obvious solute trapping effect of the segregative Zr component. Meanwhile, the Vickers hardness of HEB phase displayed the rising tendency with supercooling.

Three orthogonal ultrasounds fabricate uniform ternary Al-Sn-Cu immiscible alloy

The production of Al based monotectic alloys with uniform microstructure is usually difficult due to the large density difference between the two immiscible liquid phases, which limits the application of such alloys. Here, we apply three orthogonal ultrasounds during the liquid phase separation process of ternary Al_71.9Sn_20.4Cu_7.7 immiscible alloy. A uniform microstructure consisting of fine secondary (Sn) phase dispersed on Al-rich matrix is fabricated in the whole alloy sample with a large size of 30 × 30 × 100 mm. The numerical calculation results indicate that the coupled effect of three ultrasounds promotes the sound pressure level and consequently enlarges the cavitation zone within the alloy melt. The strong shockwaves produced by cavitation prevent the (Sn) droplets from coalescence, and keep them suspended in the parent Al-rich liquid phase. This accounts for the formation of homogeneous composite structures. Thus the introduction of three orthogonal ultrasounds is an effective way to suppress the macrosegregation caused by liquid phase separation and produce bulk immiscible alloys with uniform structures.

Zfp462 deficiency causes anxiety-like behaviors with excessive self-grooming in mice

Zfp462 is a newly identified vertebrate-specific zinc finger protein that contains nearly 2500 amino acids and 23 putative C2H2-type zinc finger domains. So far, the functions of Zfp462 remain unclear. In our study, we showed that Zfp462 is expressed predominantly in the developing brain, especially in the cerebral cortex and hippocampus regions from embryonic day 7.5 to early postnatal stage. By using a piggyBac transposon-generated Zfp462 knockout (KO) mouse model, we found that Zfp462 KO mice exhibited prenatal lethality with normal neural tube patterning, whereas heterozygous (Het) Zfp462 KO (Zfp462^+/- ) mice showed developmental delay with low body weight and brain weight. Behavioral studies showed that Zfp462^+/- mice presented anxiety-like behaviors with excessive self-grooming and hair loss, which were similar to the pathological grooming behaviors in Hoxb8 KO mice. Further analysis of grooming microstructure showed the impairment of grooming patterning in Zfp462^+/- mice. In addition, the mRNA levels of Pbx1 (pre-B-cell leukemia homeobox 1, an interacting protein of Zfp462) and Hoxb8 decreased in the brains of Zfp462^+/- mice, which may be the cause of anxiety-like behaviors. Finally, imipramine, a widely used and effective anti-anxiety medicine, rescued anxiety-like behaviors and excessive self-grooming in Zfp462^+/- mice. In conclusion, Zfp462 deficiency causes anxiety-like behaviors with excessive self-grooming in mice. This provides a novel genetic mouse model for anxiety disorders and a useful tool to determine potential therapeutic targets for anxiety disorders and screen anti-anxiety drugs.

[Retrospective clinical analysis of surgical treatment for gastric stump carcinoma]

OBJECTIVES

To investigate the clinical feature and surgical procedures of gastric stump carcinoma (GSC) and to identify the prognostic factors which influence survival rate of GSC patients.

METHODS

Clinical data of 167 patients who underwent R0 resection for gastric stump carcinoma at Chinese People's Liberation Army General Hospital between January 1990 and December 2012 was collected. There were 144 male and 23 female cases. The clinicopathological features of GSC patients were compared between those who underwent initial surgery for benign disease (GSC-B group, 78 cases) and for gastric cancer (GSC-M group, 89 cases). The analysis of therapeutic methods and survival time were also performed.t-test was used to compare the quantitative data between two groups. Pearson χ(2) test was used to compare the various clinicopathological characteristics between the two groups. Kaplan-Meier method was used to analyze the survival rate. Multivariate survival analysis was based on the Cox proportional hazard model.

RESULTS

Compared with GSC-M group, the interval time between initial gastrectomy and surgery in GSC-B group was longer ( (28.2±10.2) years vs. (10.8±1.0) years, t=15.902, P=0.001). There were 56 patients (71.8%) who received BillrothⅠ reconstruction in GSC-B group, and 49 patients (55.1%) who received BillrothⅡ reconstruction in GSC-M group, the difference of anastomosis method between the two groups was statistically significant (χ(2)=25.770, P=0.001). Compared with GSC-M group, the tumor of GSC-B group was usually located at the anastomotic site (χ(2)=6.975, P=0.031). The overall 1-, 3-, and 5-year survival rates of the 167 patients were 87%, 60%, and 41%. The 5-year survival rates for TNM stagesⅠ, Ⅱ, and Ⅲ were 65%, 43%, and 22%, respectively (P= 0.001). Multivariate analysis showed that small intestinal or esophageal infiltration (HR=1.957, 95%CI: 1.096 to 3.494, P=0.023), tumor location (HR=1.618, 95%CI: 1.104 to 2.372, P=0.014), and TNM stage (HR=2.307, 95%CI: 1.708 to 3.118, P=0.001) have independent effect on survival. The metastasis rates of perigastric lymph nodes, jejunum anastomosis and mesenteric lymph nodes were very high (56.3% and 65.2%, respectively).

CONCLUSIONS

The GSC appears earlier in patients with gastrectomy for malignant disease than those with benign disease. Appropriate curative resection including residual lymph node dissection is very important to improve the prognosis. Small intestinal or esophageal infiltration, tumor location, and TNM stage have independent effect on survival.

Self-assembly of fully addressable DNA nanostructures from double crossover tiles

DNA origami and single-stranded tile (SST) are two proven approaches to self-assemble finite-size complex DNA nanostructures. The construction elements appeared in structures from these two methods can also be found in multi-stranded DNA tiles such as double crossover tiles. Here we report the design and observation of four types of finite-size lattices with four different double crossover tiles, respectively, which, we believe, in terms of both complexity and robustness, will be rival to DNA origami and SST structures.

Dynamic evolution process of multilayer core-shell microstructures within containerlessly solidifying Fe(50)Sn(50) immiscible alloy

Multilayer core-shell structures are frequently formed in polymers and alloys when temperature and concentration fields are well symmetrical spatially. Here we report that two- to five-layer core-shell microstructures were the dominant structural morphology of a binary Fe(50)Sn(50) immiscible alloy solidified under the containerless and microgravity states within a drop tube. Three dimensional phase field simulation reveals that both the uniformly dispersive structure and the multilayer core-shells are the various metastable and transitional states of the liquid phase separation process. Only the two-layer core-shell is the most stable microstructure with the lowest chemical potential. Because of the suppression of Stokes motion, solutal Marangoni migration becomes important to drive the evolution of core-shell structures.

Efficacy of HVT-IBD vector vaccine compared to attenuated live vaccine using in-ovo vaccination against a Korean very virulent IBDV in commercial broiler chickens

The production performance, efficacy, and safety of two types of vaccines for infectious bursal disease virus (IBDV) were compared with in-ovo vaccination of Cobb 500 broiler chickens for gross and microscopic examination of the bursa of Fabricius, bursa/body weight (b/B) ratio, flow cytometry, and serologic response to Newcastle disease virus (NDV) vaccination. One vaccine was a recombinant HVT-IBD vector vaccine (HVT as for herpesvirus of turkeys) and the other was an intermediate plus live IBDV vaccine. A significant difference was detected at 21 d. Eight of 10 chickens that received the IBDV live vaccine had severe bursal lesions and a relatively low b/B ratio of 0.95, and an inhibited NDV vaccine response. On the other hand, the HVT-IBD vector vaccine resulted in mild bursal lesions and a b/B ratio of 1.89. Therefore, the live vaccine had lower safety than that of the HVT-IBD vector vaccine. To determine the protective efficacy, chickens were intraocularly challenged at 24 d. Eight of 10 chickens in the IBDV live vaccination group showed gross and histological lesions characterized by hemorrhage, cyst formation, lymphocytic depletion, and a decreased b/B ratio. In contrast, the HVT-IBD vector vaccinated chickens showed mild gross and histological lesions in three of 10 chickens with a b/B ratio of 1.36, which was similar to that of the unchallenged controls. Vaccinated chickens showed a significant increase in IBDV antibody titers, regardless of the type of vaccine used. In addition, significantly better broiler flock performance was observed with the HVT-IBD vector vaccine compared to that of the live vaccine. Our results revealed that the HVT-IBD vector vaccine could be used as an alternative vaccine to increase efficacy, and to have an improved safety profile compared with the IBDV live vaccine using in-ovo vaccination against the Korean very virulent IBDV in commercial broiler chickens.

[Clinical characteristics analysis of 120 cases of pediatric spinal cord injury without radiologic abnormality]

OBJECTIVE

To study the epidemiologic characteristics of pediatric spinal cord injury without radiologic abnormality.

METHODS

A retrospective analysis was performed and 120 cases of children with spinal cord injury without radiologic abnormality were admitted in China Rehabilitation Research Center from January 2005 to December 2014.The gender, age, causes of injury, injury condition and complication were analyzed. All cases were divided into two groups (0-7 years old and 8-13 years old) according to age.

RESULTS

One hundred and twenty cases included 31 boys (25.8%) and 89 girls (74.2%). Most of the children were 0-7 years old (96 cases, 80.0%). The top 3 causes of spinal cord injury were sports activities (60 cases, 50.0%), traffic accident (25 cases, 29.2%) and other trauma (11 cases, 12.5%). Seventy-one cases were low-energy injury (59.2%) and 49 cases were high-energy trauma (40.8%), most of low-energy injury were completely injured (56 cases, 78.9%). The complication rate was 59.2% and the top 3 complications were urinary infection (35 cases, 29.2%), hydronephrosis (12 cases, 10.0%) and pressure ulcers (10 cases, 8.3%).

CONCLUSION

It is needed to pay more attention to pediatric spinal cord injury without radiologic abnormality caused by low-energy injury, especially children aged 0-7 years old with history of slight injury, and be careful about spinal cord injury without radiologic abnormality result from high-energy damage.

CLINICAL SIGNIFICANCE OF PD-L1 EXPRESSION IN PARATHYROID CANCER

Introduction

Parathyroid carcinoma accounts for 0.5% to 5% of all cases of primary hyperparathyroidism and it is an exceedingly rare endocrine malignancy first described in 1933. Most experts recommend en bloc excision at initial surgery as the only chance for its cure. Both chemotherapy and radiotherapy have not been demonstrated to be beneficial in parathyroid carcinoma. Some patients have multiple recurrences or metastases. Therefore, new therapies are urgently needed. Inhibition of the interaction between Programmed Death Receptor 1 (PD-1) and Programmed Death Receptor Ligand 1 (PD-L1) enhances T-cell responses in vitro and mediates clinical antitumour activity.

Aim

We analysed the expression of PD-L1 in parathyroid cancer to evaluate its potential as target for immunotherapeutic strategy.

Subjects and methods

A cohort of 18 patients were diagnosed with primary or metastatic parathyroid cancer. Immunohistochemistry was performed in 18 formalin-fixed paraffin-embedded specimens using a rabbit monoclonal antibody. A 5% cut-off value was applied for PD-L1 positivity.

Results

The anti PD-L1 antibody showed a pre-dominantly membranous staining pattern in parathyroid cancer cells. Programmed Death Receptor Ligand-1 expression was found in 22.2% of all parathyroid carcinoma cases. There was no correlation between the expression of PD-L1 with lymph node metastasis, gender and age (P> 0.05).

Conclusion

This expression of PD-L1 in human parathyroid cancer suggests that patients with parathyroid cancer could profit from immunotherapeutic strategies using anti-PDL1 antibodies.

Abdominal wall endometriosis occurring after cesarean section: an underestimated complication

The aim of the study was to review patients characteristics, describe the exact anatomic locations and size of the endometriosis in the abdominal wall, and discuss the factors that may contribute to mesh use during abdominal wall endometriosis (AWE) resection.

MATERIALS AND METHODS

Patients diagnosed with AWE in their surgical scars from January 2008 to December 2014 were documented. Descriptive data was collected and analyzed.

RESULTS

A total of 95 patients with an age ranging from 26 to 48 years, with a mean age of 33.5 ?5.0 years at the time of excision were analyzed. The mean diameter of the mass was 3.25 cm in the present series with an average of 4.97 cm in the mesh group by ultrasound. A total of 18 patients had mesh therapy for fascia defect compared with 77 non-mesh therapy patients. The size of the lesions, the mean duration of symptoms for painful mass, and level of the serum CA125 were statistically different between mesh group and non-mesh group (p < 0.05). Cases of endometriosis lesions limited to the adipose layer had significant lower chance of using mesh (p < 0.05). However, adipose layer endometriosis lesions that had penetrated through the fascia layer and invaded into rectus abdominis muscle layer with/without peritoneum layer had significant higher chance of using mesh (p < 0.05).

CONCLUSIONS

The more common position for scar endometriosis may be in the adipose layer at the corner of the surgical scar. Mesh therapy should be considered before surgery when the diameter of the abdominal wall mass detected by ultrasound is more than five em and/or when the lesions invade into rectus abdominis muscle with/without peritoneum tissues from adipose and fascia layers.

Effect of intra-operative autonomic nerve stimulation on pelvic nerve preservation during radical laparoscopic proctectomy

AIM

This study assessed the effect of intra-operative electrical nerve stimulation (INS) on pelvic autonomic nerve preservation (PANP) during laparoscopic resection for rectal cancer.

METHOD

A total of 189 consecutive cases of radical laparoscopic proctectomy were included. PANP was assessed visually or with INS. Urinary function was evaluated by residual urine volume (RUV), International Prostatic Symptom Score (IPSS) and recatheterization rate. Erectile function was evaluated using the International Index of Erectile Function (IIEF-5) scale.

RESULTS

INS successfully confirmed PANP in 65 (91.5%) patients, while direct vision confirmed PANP in only 72 (61.0%) patients. Compared with the successfully confirmed patients, failed patients in the INS group exhibited higher postoperative RUV (100.0 ± 34.6 vs 25.2 ± 13.6 ml, P = 0.003), higher IPSS (7 days, 20.0 ± 8.6 vs 6.5 ± 2.4, P = 0.012; 1 month, 13.5 ± 6.0 vs 5.3 ± 1.9, P = 0.020; 6 months, 11.7 ± 5.1 vs 4.5 ± 1.7, P = 0.018), a greater number of incidences of a micturition disorder (66.7% vs 1.5%, P = 0.000), higher recatheterization rates (33.3% vs 1.5%, P = 0.017) and a lower IIEF score at 3 months (8.25 ± 0.96 vs 10.93 ± 1.99, P = 0.012) and 6 months (12.50 ± 1.29 vs 15.63 ± 1.65, P = 0.001) postoperatively. Compared with the vision group, the INS group had less deterioration in postoperative RUV (31.5 ± 26.4 vs 54.0 ± 46.7 ml, P = 0.000), lower IPSS (7 days, 7.7 ± 5.0 vs 11.0 ± 6.6, P = 0.000; 1 month, 6.0 ± 3.3 vs 7.6 ± 5.4, P = 0.012) and higher IIEF score (3 months, 10.69 ± 2.07 vs 9.42 ± 2.05, P = 0.001; 6 months, 15.36 ± 1.85 vs 13.64 ± 2.00, P = 0.000) as well as a lower incidence of urination disorders (7.0% vs 17.8%, P = 0.038).

CONCLUSION

INS is effective for the accurate evaluation of PANP during radical laparoscopic proctectomy. Combined with INS, laparoscopic proctectomy is more effective in urogenital function protection.

Bioinformatics analysis of miRNA expression profile between primary and recurrent glioblastoma

OBJECTIVE

Glioblastoma (GBM) is the most malignant brain tumor with rapid relapse. The goal of this study is to identify microRNAs (miRNAs) involved in recurrent GBM.

MATERIALS AND METHODS

miRNA transcription profile data (GSE32466) were downloaded, including 12 primary GBM samples and 12 recurrent GBM samples. Then, limma package was utilized to identify differentially expressed miRNAs (DEMs) with the criteria of false discovery rate < 0.05 and |log2 fold change| ≥ 1. Thereafter, miTarget and TargetScan databases were used to predict the potential target genes of DEMs. Regulatory co-expression network was constructed based on co-expressed genes and potential miRNA-gene pairs, and then, pathway analysis was conducted. Furthermore, database miRWalk was used to screen out known GBM-associated miRNAs from the identified DEMs.

RESULTS

A total of 71 DEMs were identified between primary and recurrent GBM samples, and 2684 potential target genes were found. Besides, regulatory co-expression network was constructed, including 12 DEMs and 81 potential target genes. These genes significantly enriched in ECM-receptor interaction, ribosome, and focal adhesion pathways, and DEMs like hsa-miR-320a, hsa-miR-139-5p, has-miR-128, hsa-miR-140-5p, and hsa-miR-146b-5p had high degree. Notably, 7 DEMs in network were known GBM-associated miRNAs recorded in database miRWalk.

CONCLUSIONS

DEMs like hsa-miR-320a, hsa-miR-139-5p, has-miR-128, hsa-miR-146b-5p, hsa-let-7c, hsa-miR-128, and hsa-let-7a might participate in recurrent GBM. These results would pave ways for further study of recurrent GBM mechanism, and for the prevention and treatment of recurrent GBM. However, more experimental verifications are required to prove these predictions.

Self-assembly of complex two-dimensional shapes from single-stranded DNA tiles

Current methods in DNA nano-architecture have successfully engineered a variety of 2D and 3D structures using principles of self-assembly. In this article, we describe detailed protocols on how to fabricate sophisticated 2D shapes through the self-assembly of uniquely addressable single-stranded DNA tiles which act as molecular pixels on a molecular canvas. Each single-stranded tile (SST) is a 42-nucleotide DNA strand composed of four concatenated modular domains which bind to four neighbors during self-assembly. The molecular canvas is a rectangle structure self-assembled from SSTs. A prescribed complex 2D shape is formed by selecting the constituent molecular pixels (SSTs) from a 310-pixel molecular canvas and then subjecting the corresponding strands to one-pot annealing. Due to the modular nature of the SST approach we demonstrate the scalability, versatility and robustness of this method. Compared with alternative methods, the SST method enables a wider selection of information polymers and sequences through the use of de novo designed and synthesized short DNA strands.

The near-field acoustic levitation of high-mass rotors

Here we demonstrate that spherical rotors with 40 mm diameter and 0-1 kg mass can be suspended more than tens of micrometers away from an ultrasonically vibrating concave surface by near-field acoustic radiation force. Their rotating speeds exceed 3000 rpm. An acoustic model has been developed to evaluate the near-field acoustic radiation force and the resonant frequencies of levitation system. This technique has potential application in developing acoustic gyroscope.

Upgrade of the electron beam ion trap in Shanghai

Over the last few years the Shanghai electron beam ion trap (EBIT) has been successfully redesigned and rebuilt. The original machine, developed under collaboration with the Shanghai Institute of Applied Physics, first produced an electron beam in 2005. It could be tuned with electron energies between 1 and 130 keV and beam current up to 160 mA. After several years of operation, it was found that several modifications for improvements were necessary to reach the goals of better electron optics, higher photon detection, and ion injection efficiencies, and more economical running costs. The upgraded Shanghai-EBIT is made almost entirely from Ti instead of stainless steel and achieves a vacuum of less than 10(-10) Torr, which helps to minimize the loss of highly changed ions through charge exchange. Meanwhile, a more compact structure and efficient cryogenic system, and excellent optical alignment have been of satisfactory. The magnetic field in the central trap region can reach up till 4.8 T with a uniformity of 2.77 × 10(-4). So far the upgraded Shanghai-EBIT has been operated up to an electron energy of 151 keV and a beam current of up to 218 mA, although promotion to even higher energy is still in progress. Radiation from ions as highly charged as Xe(53+, 54+) has been produced and the characterization of current density is estimated from the measured electron beam width.