Inhibition of Murine Cytomegalovirus Infection in Animals by RNase P-Associated External Guide Sequences.

External guide sequence (EGS) RNAs are associated with ribonuclease P (RNase P), a tRNA processing enzyme, and represent promising agents for gene-targeting applications as they can direct RNase-P-mediated cleavage of a target mRNA. Using murine cytomegalovirus (MCMV) as a model system, we examined the antiviral effects of an EGS variant, which was engineered using in vitro selection procedures. EGSs were used to target the shared mRNA region of MCMV capsid scaffolding protein (mCSP) and assemblin. In vitro, the EGS variant was 60 times more active in directing RNase P cleavage of the target mRNA than the EGS originating from a natural tRNA. In MCMV-infected cells, the variant reduced mCSP expression by 92% and inhibited viral growth by 8,000-fold. In MCMV-infected mice hydrodynamically transfected with EGS-expressing constructs, the EGS variant was more effective in reducing mCSP expression, decreasing viral production, and enhancing animal survival than the EGS originating from a natural tRNA. These results provide direct evidence that engineered EGS variants with higher targeting activity in vitro are also more effective in reducing gene expression in animals. Furthermore, our findings imply the possibility of engineering potent EGS variants for therapy of viral infections

Atomically dispersed Cu-N3 on hollow spherical carbon nitride for acetaminophen degradation: Generation of 1O2 from H2O2

Discharge of recalcitrant pharmaceuticals into aquatic systems has caused severe impacts on public health and ecosystem. Advanced oxidation processes (AOPs) are effective for eliminating these refractory pollutants, for which single-atom catalysts (SACs) become the state-of-the-art materials owing to the maximized exposure of active metal sites. In this work, hollow spherical graphitic carbon nitride (hsCN) was fabricated to incorporate copper species to develop Fenton-like catalysts for acetaminophen (ACT) removal. Through pyrolysis of supramolecular assemblies derived from melamine-Cu complex and cyanuric acid, single atom Cu-N3 sites were anchored on hsCN by N-coordination to obtain SACu-hsCN. In virtue of the atomically dispersed Cu-N3 sites as well as the hollow structure of hsCN providing smooth channels for the interactions between single Cu atoms and reactants, the optimal 5.5SACu-hsCN removed 94.8% of ACT after 180 min of Fenton-like reactions, which was superior to that of 5.5AGCu-hsCN with aggregated Cu particles on hsCN (56.7% in 180 min). Moreover, 5.5SACu-hsCN was still active after four cycles of regeneration. The mechanism investigation demonstrated that both hydroxyl radicals (OH) and singlet oxygen (1O2) contributed to ACT degradation in 5.5SACu-hsCN/H202 system, in which non-radical 1O2 played the dominant role

Characteristics and analysis of high speed InGaAs/InP uni-traveling-carrier photodiodes (UTC-PD)

With the development of broadband and high-frequency photonic systems, the photodiode with both high output power and high speed operating characteristics becomes attracti ve. The novel uni-traveling-carrier photodiode (UTC-PD) can realize these characteristics simultaneously. Compared with conventional photodiodes, this superior device improves the device performance in photonic system owing to its unique structure whose active region comprises a neutral or p-type narrow-gap light absorption layer and an undoped or slightly n-type wide-gap carrier collection layer. By adopting thi s structure, the photoresponse of UTC-PD is solely contributed by electrons whose transmit velocity is an order of magnitude faster than that of holes. As a consequence, the device demonstrates high performance of higher-speed operation as well as high-output saturation current. However, although UTC-PDs already show superior features, most of the InP-based UTC-PDs still need InGaAsP compositional graded quaternary structures at InGaAs and InP interface to smoothen the bandgap discontinuity. Consequently, the fabrication process and growth of materials will become more difficult and complicated. In order to resolve this limitation of intrinsic tradeoff between device's performance and growth as well as process complexity, a UTC-PD with dipoledoped interface layer is proposed in this work. Furthermore, a thicker collection layer of 350 nm is employed to obtain better performance. By measuring this photodiode with its dark current, series resistance, bandwidth and photocurrent, we can conclude that it shows excellent performances. To be specific, the device can reach a high 3-dB bandwidth of 570Hz under a constant optical power of 100 m Wand a reverse bias voltage of 6V.Master of Science (Electronics

Design and Experiment of an Ultrasound-Assisted Corneal Trephination System

According to the advantages of ultrasonic vibration cutting, an ultrasound-assisted corneal trepanation robotic system is developed to improve the accuracy of corneal trephination depth and corneal incision quality in corneal trephination operations. Firstly, we analyzed the reasons for the difficulty in controlling the depth of trephination in corneal transplantations from the perspective of the biomechanical properties of the cornea. Based on the advantages of ultrasonic vibration cutting, we introduced an ultrasonic-vibration-assisted cutting method for corneal trephination and analyzed the cutting mechanism. Secondly, we described the surgical demands of corneal trephination and listed the design requirements of a robotic system. Thirdly, we introduced the design details of said system, including the system’s overall structure, the ultrasound-assisted end effector, the key mechanisms of the robotic system, and the human–machine interaction interface. We designed the end effector based on ultrasonic vibration cutting and its eccentric adjustment system in an innovative way. Additionally, we then presented a procedure for robot-assisted corneal trephination. Finally, we performed several cutting experiments on grapes and porcine eyeballs in vitro. The results show that, compared with manual trephine, ultrasound-assisted corneal trephination has a better operation effect on the accuracy of corneal trephination depth and corneal incision quality

Association between systemic immunity-inflammation index and hypertension in US adults from NHANES 1999–2018

Abstract Hypertension is a disease closely related to inflammation, and the systemic immunity-inflammation index (SII) is a new and easily detectable inflammatory marker. We aimed to investigate the association between SII and hypertension risk in a adult population in the US. We utilized data from the National Health and Nutrition Examination Survey spanning from 1999 to 2018, incorporating comprehensive information from adults reporting hypertension. This included details on blood pressure monitoring, complete blood cell counts, and standard biochemical results. The SII was computed as the platelet count multiplied by the neutrophil count divided by the lymphocyte count. We employed a weighted multivariate logistic regression model to examine the correlation between SII and hypertension. Subgroup analyses were conducted to explore potential influencing factors. Furthermore, smooth curve fitting and two-piecewise logistic regression analysis were employed to describe non-linear relationships and identify inflection points. This population-based study involved 44,070 adults aged 20–85 years. Following Ln-transformation of the SII, multivariable logistic regression revealed that, in a fully adjusted model, participants in the highest quartile of Ln(SII) had a 12% increased risk of hypertension compared to those in the lowest quartile, which was statistically significant (OR:1.12; 95% CI 1.01, 1.24; P  0.05). Additionally, the association between Ln(SII) and hypertension displayed a U-shaped curve, with an inflection point at 5.89 (1000 cells/μl). Based on this research result, we found a U-shaped correlation between elevated SII levels and hypertension risk in American adults, with a inflection point of 5.89 (1000 cells)/μl). To validate these findings, larger scale prospective surveys are needed to support the results of this study and investigate potential mechanisms

Photocatalytic Degradation of Rhodamine B on Anatase, Rutile, and Brookite TiO2

This study compared the photocatalytic activities for the degradation of Rhodamine B (RhB) in aqueous solutions of anatase, rutile, and brookite TiO2. The TiO2 powders were prepared at low temperature. As compared with rutile obtained by a conventional high temperature calcination, the ruffle TiO2 prepared by the low temperature route had a smaller particle size, higher surface area, and more surface hydroxyl groups, and it gave a high photocatalytic activity. Rutile gave a faster photocatalysis reaction rate than anatase TiO2 for the same particle size and surface area. A pure brookite phase showed a lower photocatalytic activity when this was expressed in moles converted RhB per hour than the anatase and rutile phases. However, its areal photocatalytic activity expressed in moles converted RhB per hour per surface area was much higher than that of anatase and rutile TiO2

Insights into Persistent Toxic Substances in Protective Cases of Mobile Phones: Occurrence, Health Risks, and Implications

Despite the popularity of smartphones worldwide, persistent toxic substances (PTSs) in protective cases of mobile phones (PCMPs) and their health risks via direct skin contact have been ignored. This study investigated PTSs in PCMPs made in China with different materials and sales territory and their potential harm to human health. Polybrominated diphenyl ethers (PBDEs, 6.40 ng/g), new brominated flame retardants (NBFRs, 144 ng/g), organophosphate esters (OPEs, 10.1 mu g/g), short-chain chlorinated paraffins (SCCPs, 3.58 mu g/g), medium-chain chlorinated paraffins (MCCPs, 3.17 mu g/g), and heavy metals (HMs, 72.3 mu g/g) were detected. It was found that the different concentrations and compositions depend on the material, region, and use. Moreover, the raw materials used to fabricate PCMPs are of variable quality and may include recycled plastic waste. There are no standard quality specifications for PCMPs, and different materials have different properties, including specific surface area and adsorption ability. The risk assessment performed by Monte Carlo simulations indicated that the PTSs evaluated pose no health risks to the general population and may have adverse effects on individual high-exposure populations. According to the results of this work, it is suggested that more stringent global specifications for the selection of raw materials should be established, including the content and structural characteristics of PTSs, limitations on the use of additives in the production process, and the handling after use

Inhibition of Murine Cytomegalovirus Infection in Animals by RNase P-Associated External Guide Sequences.

External guide sequence (EGS) RNAs are associated with ribonuclease P (RNase P), a tRNA processing enzyme, and represent promising agents for gene-targeting applications as they can direct RNase-P-mediated cleavage of a target mRNA. Using murine cytomegalovirus (MCMV) as a model system, we examined the antiviral effects of an EGS variant, which was engineered using in vitro selection procedures. EGSs were used to target the shared mRNA region of MCMV capsid scaffolding protein (mCSP) and assemblin. In vitro, the EGS variant was 60 times more active in directing RNase P cleavage of the target mRNA than the EGS originating from a natural tRNA. In MCMV-infected cells, the variant reduced mCSP expression by 92% and inhibited viral growth by 8,000-fold. In MCMV-infected mice hydrodynamically transfected with EGS-expressing constructs, the EGS variant was more effective in reducing mCSP expression, decreasing viral production, and enhancing animal survival than the EGS originating from a natural tRNA. These results provide direct evidence that engineered EGS variants with higher targeting activity in vitro are also more effective in reducing gene expression in animals. Furthermore, our findings imply the possibility of engineering potent EGS variants for therapy of viral infections