Correction: Lu et al. Performance Analysis of Metalenses Based on Three Kinds of Phase Compensation Techniques. Nanomaterials 2021, 11, 2091.

There was an error in the original publication [...].

Characterization and preliminary safety evaluation of nano-SiO2 isolated from instant coffee.

The physiological and toxicological evaluation of nano-silicon dioxide (nano-SiO2) particles in food is important for ensuring food safety. In this study, nano-SiO2 particles isolated from five brands of instant coffee, were structurally characterized using transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, dynamic light scattering, and zeta potential analyses. Their toxicity was assessed by measuring cell viability, membrane integrity, and reactive oxygen species (ROS) levels in model gastrointestinal cells (GES-1 and Caco-2). Additionally, mortality, deformity rate, heart rate and death of whole zebra fish embryos were measured. The five types of nano-SiO2 samples comprised amorphous particles with a purity of approximately 99%, which met the food additive standard. Considering that the original particle size ranged from 10 to 50 nm, the samples were classified as nano-SiO2 food additives. Nano-SiO2 did not significantly impact the activity of GES-1 or Caco-2 cells, and no significant cell membrane damage was observed (Caco-2 cells exhibited mild micro damage); however, a slight increase in intracellular RPS levels was detected. Moreover, nano-SiO2 was found to cause head deformity, pericardial edema, yolk sac edema and tail bending. Collectively, the results show that nano-SiO2 time- and dose-dependently affects GES-1 and Caco-2 cell viability, as well as the mortality, heart rate, and abnormality rate of zebra fish embryos. Specifically, a high concentration (≥ 200 µg/mL) and long exposure time (≥ 48 h) of food additive nano-SiO2 affected GES-1, Caco-2 cells, and the gastrointestinal tract in zebra fish embryos.

Performance Analysis of Metalenses Based on Three Kinds of Phase Compensation Techniques.

The phase delays introduced by anisotropic nanounits include propagation phase delay, resonant phase delay and geometric phase delay. Various phase devices can be formed based on the metasurfaces consisting of anisotropic nanounits and the phase devices of the same kind function have different performances because of different working modes. In this paper, metalenses and vortex metalenses are chosen as examples to compare the optical performance of metasurface phase devices based on three kinds of phase compensation techniques. We design separately three kinds of metalenses and vortex metalenses using the cross nanoholes, L-shaped nanohole and V-shaped nanoholes and simulate numerically their intensity and phase distributions. Additionally, the results show the differences among these elements in structure complexity, polarization dependence, working efficiency and phase uniformity. The comparison for three kinds of metalenses clearly shows the merits of different phase compensation techniques and this work must be helpful for expanding the practical applications of metasurfaces.

Metasurface circular polarizer based on rotational symmetric nanoholes.

A circular polarizer is proposed based on a single layered metasurface. This metasurface circular polarizer is composed of L-shaped nanoholes etched on the silver film. The L-shaped nanoholes are rotational symmetric, and the special symmetric structure determines the polarization selection transmission of the metasurface. The theoretical analysis elaborates the design process of the metasurface circular polarizer. The proposed metasurface circular polarizers have good polarization selective transmittance, and more interestingly, they take on the opposite circular dichroism at different wavebands. The numerical simulations and experiment measurement confirm the circular dichroism of the proposed circular polarizers. The compact design, ultrathin thickness and available performance can expand the applications of the metasurface circular polarizers in the integrated optics.

Uniform theory of plasmonic vortex generation based on nanoholes.

In view of the wide applications of plasmonic vortices, a uniform theory of plasmonic vortex generation is advanced based on a metasurface consisting of nanometric rectangular holes. Rectangular holes may be located on one circle, two concentric circles, one spiral or two parallel spirals. The key problem in generating the plasmonic vortex is to construct a spiral phase, which can be excited by single or double holes. Theoretical analysis for generation of the plasmonic vortex is implemented in terms of the radiation model of dipoles and the propagation rule of surface plasmon polaritons. Several practical examples are presented and theoretical predictions are verified by the generated plasmonic vortices. The proposed theory is of benefit to the design of plasmonic vortex generators and the applications of plasmonic vortices.

α spiral nanoslit and the higher order plasmonic vortex generation.

In view of the conciseness of a spiral nanoslit and the limited order of the generated vortex, a kind of nanometer spiral, named α spirals, is proposed to generate a higher order plasmonic vortex. Theoretical analysis provides the basis for the advancement of an α spiral. The proposed spiral can generate the plasmonic vortex and the extreme order of the generated vortex depends on parameter α. The numerical simulations express the valid region of the plasmonic vortex generated by the α spiral. Discussions about the validity range of the α spiral nanoslit and the influence of the film material are beneficial to generate a high order vortex. This work builds a platform for the generation of the higher order plasmonic vortex using the simple spiral nanostructure and it can extend the potential applications of higher order plasmonic vortices.

Polarization controllable plasmonic focusing based on nanometer holes.

Two kinds of plasmonic lenses are proposed based on phase compensation. Each kind of plasmonic lens is comprised of four sets of nanohole arrays, and two sets of face-to-face nanohole arrays are planar symmetric. The adjustment of separation and the rotation angle of holes compensates, respectively, for the phase difference of the surface plasmon polaritons reaching to the focal spot. The different design principles make the proposed plasmonic lenses show the different polarization dependence focusing. Two or four foci of the first kind of plasmonic lens and two controllable foci focusing of the second kind of plasmonic lens can be utilized as optical switch and logic judgment. Theoretic analysis, numerical calculations and experiment measurement verify the focusing performance of our proposed plasmonic lenses. The focusing functionality and versatility of our proposed structures are helpful for extending the applications of plasmonic lenses in integrated optics.

Multifocal metalens with a controllable intensity ratio.

A multifocal metalens is proposed based on the optical metasurface consisting of subwavelength gratings etched on silver film. The larger transmission of grating makes the proposed metalens have high focusing efficiency, and the exquisite design of the metasurface enables the metalens to focus the light at multiple spots with the controllable intensity ratio. The intensity ratio of focal spots is controlled by adjusting grating structures. The numerical simulations give the good presentation, and the experiment measurement provides the favorable verification for the performance of the proposed multifocal metalens in light focusing and beam splitting. The advantages of the multifocal metalens, including simple design, compact structure, high efficiency, and the controllable focusing, are a benefit to its applications in optical integration and micromanipulation.

The sequence and de novo assembly of Oxygymnocypris stewartii genome.

Animal genomes in the Qinghai-Tibetan Plateau provide valuable resources for scientists to understand the molecular mechanism of environmental adaptation. Tibetan fish species play essential roles in the local ecology; however, the genomic information for native fishes was still insufficient. Oxygymnocypris stewartii, belonging to Oxygymnocypris genus, Schizothoracinae subfamily, is a native fish in the Tibetan plateau living within the elevation from roughly 3,000 m to 4,200 m. In this report, PacBio and Illumina sequencing platform were used to generate ~385.3 Gb genomic sequencing data. A genome of about 1,849.2 Mb was obtained with a contig N50 length of 257.1 kb. More than 44.5% of the genome were identified as repetitive elements, and 46,400 protein-coding genes were annotated in the genome. The assembled genome can be used as a reference for future population genetic studies of O. stewartii and will improve our understanding of high altitude adaptation of fishes in the Qinghai-Tibetan Plateau.

Preclinical PK/PD model for combined administration of erlotinib and sunitinib in the treatment of A549 human NSCLC xenograft mice.

AIM: Combined therapy of EGFR TKI and VEGFR TKI may produce a greater therapeutic benefit and overcome EGFR TKI-induced resistance. However, a previous study shows that a combination of EGFR TKI erlotinib (ER) with VEGFR TKI sunitinib (SU) did not improve the overall survival in patients with non-small-cell lung cancer (NSCLC). In this study we examined the anticancer effect of ER, SU and their combination in the treatment of A549 human NSCLC xenograft mice, and conducted PK/PD modeling and simulations to optimize the dose regimen. METHODS: ER (20, 50 mg·kg(-1)·d(-1)) or SU (5, 10, 20 mg·kg(-1)·d(-1)) alone, or their combination were administered to BALB/c nude mice bearing A549 tumors for 22 days. The tumor size and body weight were recorded daily. The experimental data were used to develop PK/PD models describing the quantitative relationship between the plasma concentrations and tumor suppression in different dose regimens. The models were further evaluated and validated, and used to predict the efficacy of different combination regimens and to select the optimal regimen. RESULTS: The in vivo anticancer efficacy of the combination groups was much stronger than that of either drug administered alone. A PK/PD model was developed with a combination index (φ) of 4.4, revealing a strong synergistic effect between ER and SU. The model simulation predicted the tumor growth in different dosage regimens, and showed that the dose of SU played a decisive role in the combination treatment, and suggested that a lower dose of ER (≤5 mg·kg(-1)·d(-1)) and adjusting the dose of SU might yield a better dosage regimen for clinical research. CONCLUSION: The experimental data and modeling confirm synergistic anticancer effect of ER and SU in the treatment of A549 xenograft mice. The optimal dosage regimen determined by the PK/PD modeling and simulation can be used in future preclinical study and provide a reference for clinical application.

[Effect of locomotion and feeding on metabolic mode of juvenile lenok, Brachymystax lenok (Pallas) under different water temperatures].

To investigate the effect of locomotion and feeding on the metabolic mode of juvenile lenok, Brachymystax lenok (Pallas) under different water temperatures, the pre-exercise oxygen consumption rate (MO2p), active oxygen consumption rate (MO2a), metabolic scope (MS), critical swimming speed (Uc) and swimming metabolic rate of both fasting and fed fish were measured at five temperature levels (4 degrees C, 8 degrees C, 12 degrees C, 16 degrees C and 20 degrees C) and ten flow velocities with saturated dissolved oxygen (> 8.0 mg x L(-1)). The results showed that the MO2p and MO2a of the feeding group were significantly higher (P < 0.05) than the fasting group under different temperatures, and the increases in MO2p and MO2a at 4 degrees C, 8 degrees C, 12 degrees C, 16 degrees C and 20 degrees C were 15%, 47%, 30%, 43% and 8%, and 12%, 23%, 21%, 36% and 7%, respectively. No significant differences were observed for Uc and MS between the fasting and the feeding groups (P > 0.05), but the MS showed a trend of decline with increase in water temperature. Swimming metabolic rate of fish was increased with increasing the flow velocity, and further increase of flow velocity resulted in a decline in swimming metabolic rate, and the swimming metabolic rate of the feeding group was significantly higher than that of the fasting group (P < 0.05). The metabolic rate increased with increasing the swimming speed up to 70% Uc, and then decreased with increasing the swimming speed up to Uc. It was concluded that, under certain temperature, the maximum metabolic rate was induced by exercise and feeding; the metabolic rate exhibited the additive metabolic mode before increasing to the maximum and thereafter, the metabolic rate induced by feeding reduced with decreasing the swimming metabolic rate, exhibiting the locomotion prioritized mode.

[Biological characteristics of PHA-induced CIK cells and its killing activity to K562 cells].

The purpose of study was to investigate the in vitro proliferation ability of PHA-induced CIK cells and traditionally prepared CIK cells, the effector cell level and its influence on killing activity to K562 cells, and to analyze the difference between them. The peripheral blood mononuclear cells(PBMNC) of healthy persons were isolated and divided into A and B group. The CIK cells in A group were obtained by using traditional culture method, the CIK cells in B group were prepared by PHA induction. During the cultivation, the cell survival rate and cell absolute value in the cell culture system were counted every 3 days. On day 15 of culture, the cell immunophenotype of 2 groups were detected by flow cytometry, and the ratios of CD3(+)CD56(+), CD3(+)CD8(+) and CD3(+)CD4(+) cells in total cell amount of culture system were accounted. Meantime, the killing activity to K562 cells in different effector-target ratios was detected by using CCK-8 kit between the 2 groups. The results showed that the method of preparing CIK by PHA induction promoted the cell proliferation more than that of the traditional method (P < 0.05), moreover, both the survival rate of cells in 2 groups was more than 90%. The CD3(+)CD8(+), CD3(+)CD56(+) cell ratio in 2 groups obviously increased. As compared with traditional method, the CD3(+)CD8(+) cell level in B group was enhanced (P < 0.05); but there were no statistical differences in increase of CD3(+)CD56(+) cell level and decrease of CD3(+)CD4(+) cell level between 2 groups. while the effector-target ratio is 5:1, 10:1, 20:1 and 40:1, the killing activity of PHA-induced CIK cells to K562 cells was more stronger than traditionally-prepared CIK cells (P < 0.05), moreover, along with increase of effector-target ratio, the difference of killing activity to K562 cells in 2 groups significantly increased. It is concluded that compared with traditional method for preparing CIK cells, the new way by PHA induction can increase the proliferation of CIK cells obviously, enhance the ratio of CD3(+)CD8(+) cells and strengthen the killing activity to the K562 cells. This new way provides a new source of CIK cells and reliable evidence for cyto-immune therapy of leukemia and other tumors.

Biological characteristics of PHA-induced CIK cells and its killing activity to K562 cells / 中国实验血液学杂志

The purpose of study was to investigate the in vitro proliferation ability of PHA-induced CIK cells and traditionally prepared CIK cells, the effector cell level and its influence on killing activity to K562 cells, and to analyze the difference between them. The peripheral blood mononuclear cells(PBMNC) of healthy persons were isolated and divided into A and B group. The CIK cells in A group were obtained by using traditional culture method, the CIK cells in B group were prepared by PHA induction. During the cultivation, the cell survival rate and cell absolute value in the cell culture system were counted every 3 days. On day 15 of culture, the cell immunophenotype of 2 groups were detected by flow cytometry, and the ratios of CD3(+)CD56(+), CD3(+)CD8(+) and CD3(+)CD4(+) cells in total cell amount of culture system were accounted. Meantime, the killing activity to K562 cells in different effector-target ratios was detected by using CCK-8 kit between the 2 groups. The results showed that the method of preparing CIK by PHA induction promoted the cell proliferation more than that of the traditional method (P < 0.05), moreover, both the survival rate of cells in 2 groups was more than 90%. The CD3(+)CD8(+), CD3(+)CD56(+) cell ratio in 2 groups obviously increased. As compared with traditional method, the CD3(+)CD8(+) cell level in B group was enhanced (P < 0.05); but there were no statistical differences in increase of CD3(+)CD56(+) cell level and decrease of CD3(+)CD4(+) cell level between 2 groups. while the effector-target ratio is 5:1, 10:1, 20:1 and 40:1, the killing activity of PHA-induced CIK cells to K562 cells was more stronger than traditionally-prepared CIK cells (P < 0.05), moreover, along with increase of effector-target ratio, the difference of killing activity to K562 cells in 2 groups significantly increased. It is concluded that compared with traditional method for preparing CIK cells, the new way by PHA induction can increase the proliferation of CIK cells obviously, enhance the ratio of CD3(+)CD8(+) cells and strengthen the killing activity to the K562 cells. This new way provides a new source of CIK cells and reliable evidence for cyto-immune therapy of leukemia and other tumors.

Docetaxel-loaded liposomes: preparation, pH sensitivity, pharmacokinetics, and tissue distribution.

Docetaxel (DTX), as a member of taxoid family, has been widely used in the treatment of cancers. The present study prepared pH-sensitive DTX-loaded liposomes (DTX-Lips) by thin-film dispersion method and various physico-chemical and morphological properties were examined. The pH sensitivity of in vitro DTX release and the in vivo pharmacokinetics and tissue distribution using Kunming mice were also investigated. The mean particle size and zeta potential of DTX liposomes were (277±2) nm and (-32.60±0.26) mV, respectively. Additionally, in vitro drug release study showed that the cumulative release rate was 1.3 times more at pH 5.0 than at pH 7.4, suggesting a pH-dependent release ability of DTX-Lips. Pharmacokinetic and pharmaceutical studies in comparison with Duopafei(®) showed that the half-time period (t(1/2)) and area under the curve (AUC) of DTX-Lips in mouse plasma were 1.8 times longer and 2.6 times higher, respectively, and that DTX-Lips selectively accumulated in macrophage-rich organs such as liver and spleen. These results together suggest that the DTX-Lips could be a promising formulation for the clinical administration of DTX.

[Application of Stata software to test heterogeneity in meta-analysis method].

To introduce the application of Stata software to heterogeneity test in meta-analysis. A data set was set up according to the example in the study, and the corresponding commands of the methods in Stata 9 software were applied to test the example. The methods used were Q-test and I2 statistic attached to the fixed effect model forest plot, H statistic and Galbraith plot. The existence of the heterogeneity among studies could be detected by Q-test and H statistic and the degree of the heterogeneity could be detected by I2 statistic. The outliers which were the sources of the heterogeneity could be spotted from the Galbraith plot. Heterogeneity test in meta-analysis can be completed by the four methods in Stata software simply and quickly. H and I2 statistics are more robust, and the outliers of the heterogeneity can be clearly seen in the Galbraith plot among the four methods.