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As the most valuable feature of the CRISPR system, the programmability based on Watson-Crick base pairing has been widely exploited in engineering RNA sensors. The base pairing in these systems offers a connection between the RNA of interest and the CRISPR effector, providing a highly specific mechanism for RNA detection both in vivo and in vitro. In the last decade, despite the many successful RNA sensing approaches developed during the era of CRISPR explosion, a deeper understanding of the characteristics of CRISPR systems and the continuous expansion of the CRISPR family members indicates that the CRISPR-based RNA sensor remains a promising area from which a variety of new functions and applications can be engineered. Here, we present a systematic overview of the various strategies of engineering CRISPR gRNA for programmable RNA detection with an aim to clarify the role of gRNA's programmability among the present limitations and future development of CRISPR-enabled RNA sensors. [ABSTRACT FROM AUTHOR]

Bacterial cells continuously sense and respond to their environment using their inherent signalling and gene regulatory networks. Cells are equipped with parallel signalling pathways, which can specifically cope with individual input signals, while interconnectivities between pathways lead to an enhanced complexity of regulatory responses that enable sophisticated adaptation. In principle, any cell signalling pathway may be rewired to respond to non-cognate signals by exchanging and recombining their underlying cognate signalling components. In the present article, we review the engineering strategies and use of chimaeric regulatory proteins in cell signalling pathways, especially the TCS (two-component signalling) system in bacteria, to achieve novel customized signalling or regulatory functions. We envisage that engineered chimaeric regulatory proteins can play an important role to aid both forward and reverse engineering of biological systems for many desired applications. [ABSTRACT FROM AUTHOR]

Clayey soil is an essential component of waste containment systems. The orientation of soil particles relative to gradients of heat, hydraulic pressure and stress is a significant factor as regards the stability and hydraulic conductivity of waste containment barriers. In this paper, an analytical method called Standard Deviational Ellipse Method, which is often used for point set distribution analysis in Geographical Information System (GIS), is used to analyze particle orientation quantitatively. Through the conversion and processing of soil microstructural images, the orientation angles of soil particles are herein determined and correlated spatially across planar cross-sections. This methodology is demonstrated for a selected SEM image of a clayey soil of 0.558 porosity. The results show that the predominant orientation angle of soil particle averages is 13.445° with an anisotropic ratio of 11.49°. These results indicate that the soil sample is mostly isotropic. [ABSTRACT FROM AUTHOR]

Purpose: To compare the treatment outcomes of robotic retroperitoneal lymph node dissection (R-RPLND) versus laparoscopic RPLND (L-RPLND) for clinical stage I non-seminomatous germ cell testicular tumors (NSGCTs).Materials and Methods: We retrospectively reviewed the data of patients with stage I NSGCTs who underwent robotic or laparoscopic RPLND between 2008 and 2017. Perioperative data and oncologic outcomes were reviewed and compared between the two groups. Progression-free survival was analyzed using Kaplan-Meier survival curves and compared between two groups.Results: A total of 31 and 28 patients underwent R-RPLND and L-RPLND respectively. The preoperative characteristics of the patients were comparable in the two groups. Patients in R-RPLND group had significantly shorter median operative time (140 vs. 175 minutes, P < .001), a shorter median duration to surgical drain removal (2 vs. 4 days, P = .002) and a shorter median postoperative hospital stay (5 vs. 6 days, P = .001). There were no statistical differences in intra- and post-operative complication rate between the groups and the oncologic outcomes were similar in the two groups.Conclusion: In expert hands, R-RPLND and L-RPLND were comparable in oncological parameter and morbidity rate; R-RPLND showed superiority in operation duration, median days to surgical drain removal and postoperative hospital stay for stage I NSGCTs. Multicenter and randomized studies with good power of study and sufficient follow-up duration are required to validate our result. [ABSTRACT FROM AUTHOR]

Sodium-sulfur (Na-S) batteries are attracting intensive attention due to the merits like high energy and low cost, while the poor stability of sulfur cathode limits the further development. Here, we report a chemical and spatial dual-confinement approach to improve the stability of Na-S batteries. It refers to covalently bond sulfur to carbon at forms of C-S/N-C= S bonds with high strength for locking sulfur. Meanwhile, sulfur is examined to be S1-S2 small species produced by thermally cutting S8 large molecules followed by sealing in the confined pores of carbon materials. Hence, the sulfur cathode achieves a good stability of maintaining a high-capacity retention of 97.64% after 1000 cycles. Experimental and theoretical results show that Na+ is hosted via a coordination structure (N···Na···S) without breaking the C-S bond, thus impeding the formation and dissolution of sodium polysulfide to ensure a good cycling stability. This work provides a promising method for addressing the S-triggered stability problem of Na-S batteries and other S-based batteries. [ABSTRACT FROM AUTHOR]

Recent studies have revealed that chemokine-like factor-like MARVEL transmembrane domain-containing family member 6 (CMTM6) promotes tumor progression and modulates tumor immunity by regulating programmed death-ligand 1 stability; however, its intrinsic functions and regulatory mechanisms in clear cell renal cell carcinoma (ccRCC) remain poorly understood. Here, we show that CMTM6 is upregulated in ccRCC tissues and is strongly associated with advanced tumor grades, early metastases, and a worse prognosis. CMTM6 depletion significantly impaired the proliferation, migration, and invasion of ccRCC cells in vitro and in xenograft mouse models in vivo. In addition, targeting CMTM6 promotes anti-tumor immunity, represented by increased infiltration of CD4+ and CD8+ T cells in syngeneic graft mouse models. Further research revealed that loss of CMTM6 triggered aberrant activation of DNA damage response, resulting in micronucleus formation and G2/M checkpoint arrest, finally leading to cellular senescence with robust upregulation of numerous chemokines and cytokines. Our findings show for the first time the novel role of CMTM6 in maintaining cancer genome stability and facilitating tumor-mediated immunosuppression, linking DNA damage signaling to the secretion of inflammatory factors. Targeting CMTM6 may improve the treatment of patients with advanced ccRCC. [ABSTRACT FROM AUTHOR]

Background: Type 2 diabetes mellitus (T2DM), an epidemic disease around world, has recently been identified as a risk factor for osteoporosis-associated fracture. However, there is no consensus on the best method of assessing fracture risk in patients with T2DM. The aim of this study was to evaluate the usefulness of the Osteoporosis Self-Assessment Tool for Asians (OSTA) and the Singh Index (SI) in hip fracture risk assessment in patients with T2DM. Methods: We enrolled 261 postmenopausal women with T2DM: 87 had hip fracture resulting from low-energy trauma and 174 age-matched controls had no fracture (two controls per fracture case). Bone mineral density (BMD) was measured with dual-energy X-ray absorptiometry in the lumbar spine and hip region. The SI was obtained from standard antero-posterior radiographs of the pelvis. The OSTA was calculated with a formula based on weight and age. Data were analyzed with descriptive statistics and tests of difference. Receiver operating characteristic analysis was used to determine optimum cutoff values, sensitivity, and specificity of screening methods. Discriminative abilities of different screening tools were compared with the area under the curve (AUC). Results: There were significant differences in BMD at all sites (lumbar spine, femoral neck, trochanter, and total hip) and in SI between the fracture and non-fracture groups (P < 0.05). There was no significant difference in OSTA between the groups (P > 0.05). The area under the curve was 0.747 (95% CI: 0.680-0.813) for lumbar spine BMD, 0.699 (95% CI: 0.633-0.764) for total hip BMD, 0.659 (95% CI: 0.589-0.729) for femoral neck BMD, 0.631 (95% CI: 0.557-0.704) for trochanter BMD, 0.534 (95% CI: 0.459-0.610) for OSTA, 0.636 (95% CI: 0.564-0.709) for SI, and 0.795 (95% CI: 0.734-0.857) for OSTA plus SI. The AUC for combined OSTA plus SI was significantly superior to other parameters besides BMD of the lumbar spine. Conclusions: The combination of OSTA plus SI could be a clinical alternative tool for screening of hip fracture risk in large diabetic populations. These tests are inexpensive and simple to perform and could be especially useful in areas where BMD measurement is not accessible. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy of Preoperative Aspects and Dimension Used for an Anatomical (PADUA) classification in the prediction of Warm Ischemia Time (WIT) during Laparoscopic Partial Nephrectomy (LPN). Methods: Single centre retrospective study on 402 patients who underwent LPN between January 2011 and October 2013. WIT was correlated with each characteristics of the PADUA classification. Univariate and multivariate analysis were used to evaluated the independent predictive risk factors of WIT >20 minutes. Results: The median WIT was 19.8 minutes (IQR 15-25). The PADUA risk groups (High vs Low: OR: 2.804; 95% CI 1.155-6.806; p-value <0.001; Intermediate vs Low: OR 0.971; 95% CI 0.185-5.092 p-value <0.001) and PADUA score as continuous variable (OR: 1.512; 95% CI 1.043-2.194; p-value <0.001) were the best independent risk factors of WIT >20 minutes. Another important factor related with WIT >20 minutes was a CKD stage 3 (p-value: 0.047; OR: 0.528; 95% CI:0.282-0.990). Conclusions: This study reveal that tumor' anatomical aspects may influence the WIT. The use of the nephrometry scoring systems should to be use by the surgeon in the planning of nephron sparing surgery (NSS) and should be considered for its inclusion in international guidelines. [ABSTRACT FROM AUTHOR]

We reported here a selectively additive process to fabricate nanoscale openings of an Si (111) surface from an SiO2 barrier layer. Such nanoscale openings are made for the growth of vertical III–V nanowires. The Si (111) surface protected by a patterned SiNx layer was thermally oxidized, which resulted in a selectively added SiO2 barrier layer. After removing the SiNx, nanoscale openings of the Si (111) surface were exposed for the nanowire growth. Arrays with patterned nanoholes of varied diameters from 60 nm to 334 nm have been used for position-controlled catalyst-free growth of vertical InAs nanowire arrays by metal-organic chemical vapor deposition. Correlations between the nanohole diameter and the diameter, length and growth yield of as-fabricated nanowire arrays have been investigated, showing a repeatable stability. This technique offers an alternative approach for the fabrication of novel III–V nanowire devices using vertical array configuration. A lateral thermal oxidation effect led to a smaller size of the Si opening than that of the SiNx protection nanoislands; therefore, the technique also offers a controllable way to produce nanoholes with an ultra-small diameter. [ABSTRACT FROM AUTHOR]

The aims of the present study were to investigate the effect of sodium valproate (VPA) on the sleep structures of epileptic patients and the correlation of these effects with patient weight gain. A total of 60 epileptic patients were divided into three groups: E-AED I (VPA administration for a duration of <3 months), E-AED II (VPA administration for a duration of >3 months) and ECO (without VPA) groups, for polysomnography monitoring. When the E-AED II group was compared with the E-AED I and ECO groups, non-rapid eye movement sleep phase 1 was significantly prolonged (92.10±48.24, 29.50±10.61 and 23.94±13.27 min, respectively; P<0.01), rapid eye movement sleep was significantly shortened (70.82±17.69, 116.99±12.90 and 126.19±35.01 min, respectively; P<0.01), sleep efficiency was significantly reduced (89.39±2.55, 91.98±2.53 and 91.96±3.14%, respectively; P<0.01), the number of times of that the patients awoke was significantly increased (7.25±2.86, 2.55±1.42 and 2.40±1.39, respectively; P<0.01) and the number of REM phases throughout the night was significantly reduced (P<0.01). There were no significant differences for the various sleep parameters between the E-AED I and ECO groups. Therefore, VPA is capable of inducing sleep structure disorders in epileptic patients. In addition, these disorders begin 3 months following the administration of VPA, which indicates that these disorders may be associated with VPA-induced weight gain. [ABSTRACT FROM AUTHOR]

Nowadays, microfluidics is attracting more and more attentions in the biological society and has provided powerful solutions for various applications. This paper reported a microfluidic strategy for aqueous sample sterilization. A well-designed small microchannel with a high hydrodynamic resistance was used to function as an in-chip pressure regulator. The pressure in the upstream microchannel was thereby elevated which made it possible to maintain a boiling-free high temperature environment for aqueous sample sterilization. A 120C temperature along with a pressure of 400 kPa was successfully achieved inside the chip to sterilize aqueous samples with E. coli and Staphylococcus aureus inside. This technique will find wide applications in portable cell culturing, microsurgery in wild fields, and other related micro total analysis systems. [ABSTRACT FROM AUTHOR]

The interaction mechanisms of CO2 with CH3 and H on Cu(111) surface in synthesis of acetic acid from CH4/CO2 are systematically investigated by the first-principle DFT–GGA calculations. Four possible reaction pathways are proposed, and the detailed mechanisms and kinetics are discussed. Our results show that all products are formed by gaseous CO2 and adsorbed CH3 and H through the Eley–Rideal (E–R) mechanism. It is found that the values of the activation barrier for four different pathways are in the order of CH3COO-Cu < HCOO-Cu < HOOC-Cu < CH3OCO-Cu, suggesting that CO2 insertion into Cu—CH3 bond to form CH3COO-Cu is the most advantageous in dynamics among all four reaction pathways, and the corresponding activation barrier of the rate-controlled step is 85.2kJ mol−1. The insertion of CO2 into Cu—H bond to form HCOO-Cu is secondly preferential pathway favored in dynamics. Therefore, H3CCOO is the main product, HCOO is a primary side product, and H3COCO are not obtained as it is inhibited by dynamics in comparison with other pathways. Above calculated results are in accordance with the experimental results, which can provide a new theoretical guidance for the direct synthesis of oxygenated compounds from CH4 and CO2. [ABSTRACT FROM AUTHOR]

Background: Although metastasis of clear cell renal cell carcinoma (ccRCC) is basically observed in late stage tumors, T1 stage metastasis of ccRCC can also be found with no definite molecular cause resulting inappropriate selection of surgery method and poor prognosis. Notch signaling is a conserved, widely expressed signal pathway that mediates various cellular processes in normal development and tumorigenesis. This study aims to explore the potential role and mechanism of Notch signaling in the metastasis of T1 stage ccRCC. Methodology/Principal Findings: The expression of Notch1 and Jagged1 were analyzed in tumor tissues and matched normal adjacent tissues obtained from 51 ccRCC patients. Compared to non-tumor tissues, Notch1 and Jagged1 expression was significantly elevated both in mRNA and protein levels in tumors. Tissue samples of localized and metastatic tumors were divided into three groups based on their tumor stages and the relative mRNA expression of Notch1 and Jagged1 were analyzed. Compared to localized tumors, Notch1 expression was significantly elevated in metastatic tumors in T1 stage while Jagged1 expression was not statistically different between localized and metastatic tumors of all stages. The average size of metastatic tumors was significantly larger than localized tumors in T1 stage ccRCC and the elevated expression of Notch1 was significantly positive correlated with the tumor diameter. The functional significance of Notch signaling was studied by transfection of 786-O, Caki-1 and HKC cell lines with full-length expression plasmids of Notch1 and Jagged1. Compared to the corresponding controls, all cell lines demonstrated significant promotion in cell proliferation and migration while cell cycle remained unaffected. Conclusions/Significance: High-level expression of Notch signaling increased the risk of metastasis in T1 stage ccRCC by stimulating the proliferation and migration of tumor cells, which may be helpful for the selection of suitable operation method and prognosis of ccRCC. [ABSTRACT FROM AUTHOR]

Abstract: The formation mechanism of CH3O by the adsorption and decomposition of CH3OH on clean and oxygen-precovered Cu2O(111) surface has been investigated with density functional theory method together with the periodic slab models. Two possible formation pathways of CH3O by CH3OH decomposition on oxygen-precovered (Opre) Cu2O(111) surface were proposed and discussed. One is the O–H bond-cleavage of CH3OH with H migration to Opre to form CH3O; the other is the C–O bond-scission of CH3OH with CH3 migration to Opre leading to CH3Opre. The calculated results show that the O–H bond-breaking path has the lowest activation barrier 26.8kJmol−1, the presence of oxygen-precovered on Cu2O(111) surface exhibits a high surface reactivity toward the formation of CH3O by the O–H bond-cleavage of CH3OH, and reduce the activation barrier of O–H bond-cleavage. The C–O bond-breaking path was inhibited by dynamics, suggesting that the O atom of CH3O is not from the oxygen-precovered, but comes from the O of CH3OH. Meanwhile, the calculated results give a clear illustration about the formation mechanism of CH3O in the presence of oxygen and the role of oxygen at the microscopic level. [ABSTRACT FROM AUTHOR]

Purpose: To present a new technique of retroperitoneoscopic Anderson-Hynes dismembered pyeloplasty (AHDP) in infants and children with ureteropelvic junction obstruction (UPJO) based on our clinical experience.Methods: From March 2003 to February 2007, retroperitoneoscopic AHDP was performed in 60 (44 boys and 16 girls) UPJO infants and children with a three-port lateral retroperitoneal approach. The retroperitoneal space was entered via a 1-cm longitudinal incision beneath the 12th rib and further developed by a glove balloon. Video-retroperitoneoscopy was undertaken with a 5-mm laparoscope between the mid axillary line and 1 cm away from the superior border of iliac crest. Dismembered pyeloplasty was carried out with the Anderson-Hynes anastomosis where 5-0 or 6-0 vicryl sutures were over a double-J ureteric stent. Anastomosis was completed with freehand intracorporeal suture techniques. Follow-up studies were conducted by intravenous urography and renal ultrasonography.Results: Among the 60 patients (62 sides) with retroperitoneoscopic AHDP, only the first two cases were converted to open surgery due to difficulties in developing the retroperitoneal space, and the remaining cases succeeded. The average operative time was 70 +/- 12.6 min (ranging from 55 to 130 min), the average estimated blood loss was 10 +/- 2.2 ml (ranging from 5 to 20 ml), and the average postoperative hospital stay was 7 +/- 1.3 days (ranging from 3 to 15 days). Aberrant artery vessel was intraoperatively observed in seven patients. Postoperative urinary leakage occurred in two patients, but spontaneously disappeared on the 6th and 11th days after the surgery, respectively; and one of them underwent open surgery for recurrent UPJO 8 months later. During an average follow-up period of 24 months, we performed radiographic assessment by intravenous urography and found that all the cases showed good results except the patient who underwent open surgery later.Conclusions: Our experience with retroperitoneoscopic AHDP demonstrates that this technique is safe, effective and time saving for treating UPJO in infants and children. [ABSTRACT FROM AUTHOR]

Associate Editor Ash Tewari Editorial Board Ralph Clayman, USA Inderbir Gill, USA Roger Kirby, UK Mani Menon, USA OBJECTIVE To report our experience with the treatment of pelvi-ureteric junction obstruction (PUJO) using the retroperitoneal laparoscopic Hellström (RLH) technique to relocate the crossing vessel. PATIENTS AND METHODS We used the RLH technique selectively in eight patients with PUJO from an aberrant crossing vessel, according to observations during surgery. The crossing vessel was mobilized and embedded in the generous pelvic wall with 4–0 polyglactin sutures to relieve the PUJO. Follow-up studies included intravenous urography, ultrasonography and renal functional scintigraphy at 1 month after surgery and every 3 months thereafter. RESULTS The mean (range) operative duration was 45 (40–60) min; the blood loss was negligible. Crossing vessels were identified to be anterior to the renal pelvis in two patients and posterior in six. The hospital stay after surgery was 5 (4–7) days. No paregoric was required after surgery. The collecting systems were intact and no JJ stent was required in any patient. The mean (range) follow-up was 13.6 (12–15) months. In all patients the obstruction was resolved or significantly improved, and there were no complications, e.g. urine leakage and infection. A long-term follow-up is mandatory. CONCLUSIONS The RLH technique is a minimally invasive alternative for patients with PUJO caused by a crossing vessel. Embedding the crossing vessels in the pelvic wall is feasible and safe for such patients; empirical judgement during surgery is prudent for success. [ABSTRACT FROM AUTHOR]

A distributed-feedback (DFB) laser and a high-speed electroabsorption (EA) modulator are integrated, on the basis of the selective area MOVPE growth (SAG) technique and the ridge waveguide structure, for a 10 Gbit s-1 optical transmission system. The integrated DFB laser/EA modulator device is packaged in a compact module with a 20% optical coupling efficiency to the single-mode fibre. The typical threshold current is 15 mA, and the side-mode suppression ratio is over 40 dB with the single-mode operation at 1550 nm. The module exhibits 1.2 mW fibre output power at a laser gain current of 70 mA and a modulator bias voltage of 0 V. The 3 dB bandwidth is 12 GHz. A dynamic extinction ratio of over 10 dB has been successfully achieved under 10 Gbit s-1 non-return to zero (NRZ) operation, and a clearly open eye diagram is obtained. [ABSTRACT FROM AUTHOR]

Increasing the effective voltage is proposed to improve applied-field magnetoplasmadynamic thrusters (AF-MPDTs) efficiency. An analytical model for both effective voltage and thrust is presented and discussed on the basis of the generalized Ohm’s law. According to such a model, the effective voltage contributes to plasma acceleration and measures can be taken to affect it, including adjusting the fraction of cathode gas injection, applied magnetic field strength and discharge current. In order to verify the model, experiments were conducted on the conditions of stable operation of a 10 kW AF-MPDT. The results showed that discharge current affected thruster efficiency mainly by enhancing the back electromotive effect in plasma acceleration processes. The thrust efficiency was enhanced by an average of 9.1% by raising discharge current from 90 A to 180 A. The fraction of cathode gas injection mainly affected the resistive and Hall effect, and the thrust efficiency was enhanced by an average of 7.3% by increasing the fraction of cathode gas injection from 0.1 to 0.9. The applied magnetic field influenced the thruster performance by enhancing both the resistive and Hall effect and the back electromotive effect. The thrust efficiency was increased by an average of 3.0% by raising the applied magnetic field strength from 0.05 T to 0.17 T. It was found that the plasma acceleration of AF-MPDT was dominated by effective voltage, and increasing the effective voltage was an effective and comprehensive way to improve thruster performance. [ABSTRACT FROM AUTHOR]