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Because intelligent hydrogels have good biocompatibility, a rapid response, and good degradability as well as a stimulus response mode that is rich, hydrophilic, and similar to the softness and elasticity of living tissue, they have received widespread attention and are widely used in biomedical engineering. In this article, we conduct a systematic review of the use of smart hydrogels in biomedical engineering. First, we introduce the properties and applications of hydrogels and compare the similarities and differences between traditional hydrogels and smart hydrogels. Secondly, we summarize the intelligent hydrogel types, the mechanisms of action used by different hydrogels, and the materials for preparing different types of hydrogels, such as the materials for the preparation of temperature-responsive hydrogels, which mainly include gelatin, carrageenan, agarose, amylose, etc.; summarize the morphologies of different hydrogels, such as films, fibers and microspheres; and summarize the application of smart hydrogels in biomedical engineering, such as for the delivery of proteins, antibiotics, deoxyribonucleic acid, etc. Finally, we summarize the shortcomings of current research and present future prospects for smart hydrogels. The purpose of this paper is to provide researchers engaged in related fields with a systematic review of the application of intelligent hydrogels in biomedical engineering. We hope that they will get some inspiration from this work to provide new directions for the development of related fields.

Using optical coherence tomography angiography, we found an increase in the blood flow in regional macular without significant changes in the optic disk in patients with glaucoma after a moderate exercise regime.To investigate the effect of moderate exercise on optic nerve and macular perfusion in glaucoma patients.Overall, 25 eyes of 25 patients with primary open angle glaucoma and 22 eyes of 22 normal subjects were included in the glaucoma and control groups, respectively. Foveal avascular zone parameters, whole and regional vessel density (VD) in the superficial layer of macula, VDs in the radial peripapillary capillary layer of the optic nerve head, intraocular pressure, and cardiovascular parameters were measured using optical coherence tomography angiography before, immediately after, and 30 minutes after a 20-minute run at moderate speed.In the glaucoma group, macular superficial VD of the whole image, parafovea, and superior and nasal regions were higher after 30 minutes of rest (44.049±5.704, 47.238±5.741, 48.692±6.648, and 47.852±5.078) than immediately after exercise (43.229±5.867, 46.334±5.984, 47.840±6.895, 46.793±5.238, P0.05). The VD in the temporal and nasal regions was higher 30 minutes after exercise (45.105±5.512 and 47.852±5.078) than before exercise (44.265±5.803 and 46.750±5.639, P0.05). The intraocular pressure decreased immediately after exercise (14.20±2.51 and 14.51±2.96 mmHg for glaucoma and controls, respectively) but was restored after 30 minutes of rest (15.84±3.57 mmHg for glaucoma and 16.50±2.25 mmHg for controls) in both groups ( P0.001). Cardiovascular parameters were similar in both groups.Moderate physical exercise for 20 minutes increased blood flow in the macula region without significant change to the optic nerve and lowered intraocular pressure in glaucoma and normal subjects. The benefit of these findings to glaucoma patients needs further study.

Background To evaluate the interocular differences of the peripapillary structural and vascular parameters and that of association with axial length (AL) in participants with myopic anisometropia using swept-source optical coherence tomography (SS-OCT). Methods This prospective cross-sectional study included 88 eyes of 44 participants. Eyes were classified into the longer and the shorter eye group according to ALs. The β- and γ-parapapillary atrophy (PPA) areas, Bruch’s membrane opening distance (BMOD), border length (BL), and border tissue angle (BTA) were measured manually. MATLAB software determined peripapillary choroidal vascularity index (CVI) and choroidal thickness (CT) values in superior, nasal, inferior, and temporal. Results The interocular difference in spherical equivalent (SE) was highly correlated with that of the AL. The β- and γ-PPA areas, BMOD, and BL were greater in longer eyes. The mean and inferior peripapillary CVI and the mean, superior, and inferior peripapillary CT were lower in the longer eye group. The interocular difference in AL was significantly positively correlated with the γ-PPA area and BL and negatively correlated with the temporal CVI and mean, inferior, and temporal peripapillary CT. There was an independent correlation between the interocular differences in AL and the γ-PPA area, inferior and temporal peripapillary CT. Conclusions Significant differences between both groups were detected in most peripapillary parameters. The γ-PPA area, BL, and peripapillary CVI and CT were sensitively affected by the elongation of AL. The characteristics of peripapillary parameters may be useful in the prediction of AL elongation.

Background To investigate short-term choroidal structural and vascular changes after epiretinal membrane (ERM) surgery. Methods In this retrospective study, 65 patients with unilateral ERM underwent pars plana vitrectomy combined with cataract surgery and were examined one day before surgery and one week, one month, and three months after surgery. Choroidal thickness (CT) and choroidal vascular index (CVI) were evaluated using horizontal enhanced depth imaging optical coherence tomography (EDI-OCT) scans and were further calculated using semi-automatic algorithms using MATLAB R2017a. Results Preoperatively, CVI was higher in eyes with ERM (61.70 ± 5.17%) than in fellow eyes (59.99 ± 5.26%). CVI increased significantly at one week after surgery (62.14 ± 5.02%) and decreased at 1 and 3 months after surgery (60.76 ± 4.97% and 60.4 ± 4.83%, respectively). The change was pronounced in the nasal region (p p p Conclusions Short-term postoperative variations in the choroid have been demonstrated in eyes with ERM. This may be related to the release of macular traction. CVI assessment using EDI-OCT may be a useful tool for investigating choroidal structural changes accompanying ERM and postoperative period.

Engineering biological systems to test new pathway variants containing different enzyme homologs is laborious and time-consuming. To tackle this challenge, a strategy was developed for rapidly prototyping enzyme homologs by combining cell-free protein synthesis (CFPS) with split GFP. This strategy featured two main advantages: 1) dozens of enzyme homologs were parallelly produced by CFPS within hours, and 2) the expression level and activity of each homolog was determined simultaneously by using the split GFP assay. As a model, this strategy was applied to optimize a 3-step pathway for nicotinamide mononucleotide (NMN) synthesis. Ten enzyme homologs from different organisms were selected for each step. Here, the most productive homolog of each step was identified within 24 h rather than weeks or months. Finally, the titer of NMN was increased to 1213 mg/L by improving physiochemical conditions, tuning enzyme ratios and cofactor concentrations, and decreasing the feedback inhibition, which was a more than 12-fold improvement over the initial setup. This strategy would provide a promising way to accelerate design-build-test cycles for metabolic engineering to improve the production of desired products. This article is protected by copyright. All rights reserved.

Background Treatment options for refractory metastatic colorectal cancer (mCRC) were limited. Anlotinib is a novel multitarget tyrosine kinase inhibitor. ALTER0703 study was conducted to assess efficacy and safety of anlotinib for patients with refractory mCRC. Materials and Methods This was a multicenter, double-blinded, placebo-controlled, randomized phase III trial involving 33 hospitals in China. Patients had taken at least two lines of therapies were 2:1 randomized to receive oral anlotinib (12 mg/day; days 1–14; 21 days per cycle) or placebo, plus best supportive care. Randomization was stratified by previous VEGF-targeting treatments and time from diagnosis to metastases. The primary endpoint was overall survival (OS). The secondary endpoints were progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), quality of life (QoL), and safety. Results A total of 419 patients (anlotinib: 282; placebo: 137) were treated from December 2014 to August 2016. The median PFS was improved in anlotinib group (4.1 months; 95% confidence interval [CI], 3.4–4.5) over placebo group (1.5 months; 95% CI, 1.4–1.5), with a hazard ratio (HR) of 0.34 (95% CI, 0.27–0.43; p < .0001). However, median OS was similar between two groups (8.6 months; 95% CI, 7.8–9.7 vs. 7.2 months; 95% CI, 6.2–8.8; HR, 1.02; p = .870). Improvements of ORR and DCR were observed in anlotinib over placebo. The most common grade ≥ 3 anlotinib related adverse events were hypertension (20.92%), increased γ-GT (7.09%), and hand-foot skin reaction (6.38%). Conclusion Anlotinib was tolerated in Chinese patients with refractory mCRC. Although OS did not reach significant difference, anlotinib still provided clinical benefits by substantially prolonged PFS in these patients. Implications for Practice In this randomized clinical trial that included 419 patients with refractory metastatic colorectal cancer, substantial prolonged in progression-free survival was noted in patients who received anlotinib compared with those given placebo. Improvements on objective response rate and disease control rate was also observed in anlotinib group. However, overall survival was similar between the two groups. In a word, in third-line or above treatment of Chinese patients with refractory metastatic colorectal cancer, anlotinib provided clinical benefit by significantly prolonged progression-free survival.

Recombinant luminescent Escherichia coli strains could be used to detect the toxicity of pure or mixed contaminants as a light-off sensor. In this work, the lux operon of Photobacterium phosphoreum T3 was identified for the first time. Recombinant luminescent E. coli strains were constructed via expressing the lux operons of P. phosphoreum T3 and Vibrio qinghaiensis Q67 in E. coli MG1655, and the optimal protectant containing 10% (w/v) trehalose and 4% sucrose was used to prepare the freeze-dried recombinant luminescent E. coli cells. Then, these freeze-dried E. coli cells were subjected to acute toxicity detection. The results showed that luminescent E. coli strains displayed sensitive toxic responses to BPA, nFe

To investigate the characteristics of the optic nerve head (ONH) in myopia using swept-source optical coherence tomography (SS-OCT).Participants were divided into three groups according to the axial length (AL). The optic disc morphology, retinal nerve fiber layer (RNFL) thickness, and radial peripapillary capillary (RPC) vessel density (VD), optic disc tilt, rotation, Bruch's membrane opening distance (BMOD), border length (BL), border tissue angle, focal lamina cribrosa (LC) defects, β- and γ-zone peripapillary atrophy (PPA), microvasculature dropout (MvD), choroidal thickness (CT), and the choroidal vascularity index (CVI) were compared. Linear regression analysis evaluated relationships between spherical equivalent, AL, and ONH parameters.One hundred five, 98, and 118 eyes were included in groups 1, 2, and 3, respectively. With AL increasing, the mean, superior and temporal CT, central mean and temporal, pericentral mean, inferior and nasal RPC VD, and temporal CVI decreased, whereas the mean and temporal RNFL thickness, optic disc, RIM and β-PPA area, presence and area of γ-PPA, BMOD and BL increased. Compared to other groups, group 3 depicted a larger cup area, more focal LC defect and total and juxtapapillary MvD; a lower central superior, inferior and nasal, pericentral superior, and temporal RPC VD. Group 1 demonstrated more tilted disc, larger inferior and nasal CT, mean, superior, inferior, and nasal CVI.Myopia eyes have larger ONH changes, PPAs, regional RNFL, and MvD, but smaller regional CTs, RPC VD, and CVIs. SS-OCT may be useful in detecting ONH variations during myopia.

A composite of cobalt tetracarboxyl phthalocyanine and amino-functionalized manganese octahedral molecular sieve (CNOMS-2) was synthesized in a simple way, and applied for degrading diclofenac in aqueous media by catalyzing of peroxymonosulfate heterogeneously. The experiment results revealed that the CNOMS-2/PMS system was highly efficient for DCF degradation in the pH range of 5-9, and the mechanism involved the generation of OH, SO4⁻ and 1O2 by the activation of PMS. The main reactive oxygen species was found to be 1O2 by radical scavenging experiments and electron paramagnetic resonance (EPR) spectroscopy. Further, a carboxylation product of DCF at m/z 340 was found to be a prominent intermediate of the reaction in this system specially, as determined by LC-MS/MS. The reusability and ion leaching concentrations under different pH were also examined to determine the application prospects of the catalyst.

Manganese oxide octahedral molecular sieve (OMS-2) and a series of OMS-2 doped with Co, Cu, and Ce were prepared via a solvent-free method, and tested in heterogeneous activation of peroxymonosulfate (PMS) for diclofenac (DCF) degradation in aqueous solutions. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), N2 adsorption/desorption isotherms, Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and X-ray photoelectron spectroscopy (XPS) were used to characterize the properties of those materials. It was found that (Co + Ce)-OMS-2 seemed to be most efficient and had the best adsorption capacity, which may due to most abundant lattice oxygen and more macropore than other materials caused by cerium ions enter into the channel. Results from XPS suggested that the highly catalytic efficiency possible involved the activation of PMS to sulfate and hydroxyl radical meditated by the redox pair of Mn(IV)/Mn(III) and Co(III)/Co(II) in catalysts. Keywords: Manganese oxide octahedral molecular sieve, Diclofenac, Peroxymonosulfate

A facile three-step photo-deposition method was applied to successfully synthesize Ag and AgI modified ZnO composites (AgI/Ag/ZnO). Under visible-light irradiation, the composites enhanced the photocatalytic efficiency of Naproxen (NPX) degradation as the Ag contents increased. 100 % NPX could be removed in 60 min when AgI/Ag/ZnO (75 %) was the catalyst. Different initial pH, alongside the addition of NO3− and SO42− had little impact, but Cl− could accelerate the degradation rate. O2− and h+ played a significant role in the photocatalysis process. Several byproducts were predicted by DFT-software calculation and verified by LC–MS/MS. The cycling experiments showed that the removal rate decreased after the first run due to the leaching of Ag+. The removal rate kept stable after the next two reactions.

Introduction: Primary keratoconus is a non-inflammatory corneal ectasia disease with an unknown cause. Nowadays, the most widely used treatment method is corneal collagen crosslinking based on the Dresden protocol. Due to the long surgery time, we have been searching for a new method which cost less time in surgery. Methods: A retrospective, observational cohort study was used. A total of 31 participants (59 eyes) with primary keratoconus were collected. Twelve of them (24 eyes) used the standard Dresden protocol, and the remaining 19 (35 eyes) used a higher-energy accelerated corneal collagen cross-linking method. Application of riboflavin solution to the de-epithelialized cornea for 10 min, then the cornea is UVA irradiated (wavelength, 365 nm and power, 30 mW/cm2) for another 3.55 min, and the total irradiation energy is 6.4J/cm2. Participants were followed up for 12 months after surgery and underwent complete examinations at 3, 6, and 12 months in predetermined windows of time. The examinations items include routine ophthalmological examination, uncorrected vision acuity (UCVA), best corrected visual acuity (BCVA), refraction, corneal curvature, the elevation of the thinnest point on front surface and back surface (F Ele Th, B Ele Th), the thickness of the thinnest point of the cornea (CT), and the density of the corneal endothelial cells (ECD). The independent sample t-test method was used to compare the changes of the parameters of the standard Dresden protocol and the higher-energy accelerated corneal collagen cross-linking. Results: In the A-CXL treatment group, the maximum keratometry value decreased by 1.48D from baseline, UCVA improved by an average of 0.07 logarithm of the minimum angle of resolution (logMAR) units, BCVA improved by an average of 0.15 logarithm of the minimum angle of resolution (logMAR) units. All of those are similar to standard Dresden protocol group. There were no significant changes in endothelial cell count and thickness of cornea 1 year after treatment. Conclusions: In this study, we found that accelerated corneal collagen cross-linking under 6.4J energy has a similar surgical effect as corneal collagen cross-linking under the Dresden protocol, and did not cause more adverse events.

Diclofenac (DCF) control measures have become an area of increased interest for environmental researchers due to the high environmental concentration and risk of DCF. Adsorption seems to be promising for DCF removal from the aqueous phase because of its specific superiority in comparison with biodegradation, membrane separation, and advanced oxidation or reduction. In this study, OMS-2 and metal-doped OMS-2 ((Me-OMS-2, with Me = Co, Cu or Ce) were prepared and tested as adsorbents for the removal of DCF. It was evident that the maximum adsorption capacity and rate of Ce-OMS-2 were much higher than those of the other adsorbents, which could be attributed to its large specific surface area and stereoscopic aperture structure. The experimental data are fitted the pseudo-second-order model, the Elovich equation and the Langmuir model well; moreover, the process is an endothermic and spontaneous thermodynamic process, during which the entropy increased, based on the experimental results, indicating that chemisorption was dominant during the DCF adsorption process onto Ce-OMS-2. By the integral of the peak deconvoluted from the XPS spectrum, the ratio of Mn3+/Mn4+ increased from 0.393 to 0.407, revealing that Mn(IV) is rarely reduced into Mn(III) during the DCF adsorption process.

Deform-3d software was used to conduct numerical simulation on the spinning forming process of inner and outer teeth to study the strain distribution and material flow law during the spinning forming process. The influence of mandrel rotation speed and roller feed speed on the forming quality of inner and outer teeth profile was studied. The results show that the best forming quality of the spinning parts can be obtained under the combination of the process parameters of the mandrel rotation speed of 150r/min and the roller feed speed of 110mm/min. Compared with the experimental results, the maximum relative errors of inner and outer teeth wall thickness were 2.03% and 1.78%, which verified the reliability of the finite element model. The results can provide guidance for the finite element simulation and production of inner and outer teeth spinning forming process.