Targeted Therapy of Ischemic Stroke via Crossing the Blood-Brain Barrier Using Edaravone-Loaded Multiresponsive Microgels

Ischemic stroke, as a prevalent neurological disorder, often results in rapid increases in the production of reactive oxygen species (ROS) and inflammatory factors in the focal ischemic area. Though edaravone is an approved treatment, its effect is limited due to its weak ability to cross the blood-brain barrier (BBB) and short half-life. Other effective pharmacological treatment options are clearly lacking. In this study, PNIVDBrF-3-Eda (also named MG-3-Eda) was prepared using a thermo- and pH dual-responsive PNIVDBrF microgel. These were designed with a positively charged network, as synthesized by simultaneous quaternization cross-linking and surfactant-free emulsion copolymerization, to be loaded with the negatively charged edaravone. We then investigated whether such a targeted delivery of edaravone could provide enhanced neuroprotection. Cytotoxicity assays confirmed that the microgel (<1 mg/mL) exhibited promising cytocompatibility with no remarkable effect on cell viability, cell cycle regulation, or apoptosis levels. In vitro and in vivo experiments demonstrated that the microgels could successfully penetrate the blood-brain barrier where efficient BBB crossing was observed after disruption of the BBB due to ischemic injury. This enabled MG-3-Eda to target the cerebral ischemic area and achieve local release of edaravone. Treatment with MG-3-Eda significantly reduced the cerebral infarct area in transient middle cerebral artery occlusion (tMCAO) mice and significantly improved behavioral scores. MG-3-Eda treatment also prevented the reduction in NF200 expression, a neuronal marker protein, and attenuated microglia activation (as detected by Iba1) in the local ischemic area via local antioxidant and anti-inflammatory effects. A superior neuroprotective effect was noted for MG-3-Eda compared to that for free edaravone. Our results indicate that MG-3-Eda administration represents a clear potential treatment for cerebral ischemia via its targeted delivery of edaravone to ischemic areas where it provides significant local antioxidant and anti-inflammatory effects.

Antagonistic Skin Toxicity of Co-Exposure to Physical Sunscreen Ingredients Zinc Oxide and Titanium Dioxide Nanoparticles

Being the main components of physical sunscreens, zinc oxide nanoparticles (ZnO NPs) and titanium dioxide nanoparticles (TiO₂ NPs) are often used together in different brands of sunscreen products with different proportions. With the broad use of cosmetics containing these nanoparticles (NPs), concerns regarding their joint skin toxicity are becoming more and more prominent. In this study, the co-exposure of these two NPs in human-derived keratinocytes (HaCaT) and the in vitro reconstructed human epidermis (RHE) model EpiSkin was performed to verify their joint skin effect. The results showed that ZnO NPs significantly inhibited cell proliferation and caused deoxyribonucleic acid (DNA) damage in a dose-dependent manner to HaCaT cells, which could be rescued with co-exposure to TiO₂ NPs. Further mechanism studies revealed that TiO₂ NPs restricted the cellular uptake of both aggregated ZnO NPs and non-aggregated ZnO NPs and meanwhile decreased the dissociation of Zn²⁺ from ZnO NPs. The reduced intracellular Zn²⁺ ultimately made TiO₂ NPs perform an antagonistic effect on the cytotoxicity caused by ZnO NPs. Furthermore, these joint skin effects induced by NP mixtures were validated on the epidermal model EpiSkin. Taken together, the results of the current research contribute new insights for understanding the dermal toxicity produced by co-exposure of different NPs and provide a valuable reference for the development of formulas for the secure application of ZnO NPs and TiO₂ NPs in sunscreen products.

Anti-pathogen stainless steel combating COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exhibits strong stability on conventional stainless steel (SS) surface, with infectious virus detected even after two days, posing a high risk of virus transmission via surface touching in public areas. In order to mitigate the surface toughing transmission, the present study develops the first SS with excellent anti-pathogen properties against SARS-COV-2. The stabilities of SARS-CoV-2, H1N1 influenza A virus (H1N1), and Escherichia coli (E.coli) on the surfaces of Cu-contained SS, pure Cu, Ag-contained SS, and pure Ag were investigated. It is discovered that pure Ag and Ag-contained SS surfaces do not display apparent inhibitory effects on SARS-CoV-2 and H1N1. In comparison, both pure Cu and Cu-contained SS with a high Cu content exhibit significant antiviral properties. Significantly, the developed anti-pathogen SS with 20 wt% Cu can distinctly reduce 99.75% and 99.99% of viable SARS-CoV-2 on its surface within 3 and 6 h, respectively. In addition, the present anti-pathogen SS also exhibits an excellent inactivation ability for H1N1 influenza A virus (H1N1), and Escherichia coli (E.coli). Interestingly, the Cu ion concentration released from the anti-pathogen SS with 10 wt% and 20 wt% Cu was notably higher than the Ag ion concentration released from Ag and the Ag-contained SS. Lift buttons made of the present anti-pathogen SS are produced using mature powder metallurgy technique, demonstrating its potential applications in public areas and fighting the transmission of SARS-CoV-2 and other pathogens via surface touching.

ALBERT-BPF: a book purchase forecast model for university library by using ALBERT for text feature extraction

Purpose

The purpose of this research is to achieve automatic and accurate book purchase forecasts for the university libraries and improve efficiency of manual book purchase.

Design/methodology/approach

The authors presented a Book Purchase Forecast model with A Lite BERT(ALBERT-BPF) to achieve their goals. First, the authors process all the book data to unify format of books' features, such as ISBN, title, authors, brief introduction and so on. Second, they exploit the book order data to label all books supplied by booksellers with “purchased” or “non-purchased”. The labelled data will be used for model training. Last, the authors regard the book purchase task as a text classification problem and present a model named ALBERT-BPF, which applies ALBERT to extract text features of books and BPF classification layer to forecast purchased books, to solve the problem.

Findings

The application of deep learning in book purchase task is effective. The data the authors exploited are the historical book purchase data from their university library. The authors’ experiments on the data show that ALBERT-BPF can seek out the books that need to be purchased with an accuracy of over 82%. And the highest accuracy reached is 88.06%. These indicate that the deep learning model is sufficient to assist the traditional manual book purchase way.

Originality/value

This research applies ALBERT, which is based on the latest Natural Language Processing (NLP) architecture Transformer, to library book purchase task.

Human amniotic fluid derived-exosomes alleviate hypoxic encephalopathy by enhancing angiogenesis in neonatal mice after hypoxia

Neonatal hypoxic encephalopathy is a type of central nervous system dysfunction manifested by high mortality and morbidity. Exosomes play a crucial role in neuroprotection by enhancing angiogenesis. The objective of this study was to investigate the effect of human amniotic fluid-derived exosomes (hAFEXOs) on functional recovery in neonatal hypoxic encephalopathy. The transwell assay, scratch wound healing assay, and tube formation assay were used to evaluate the effect of hAFEXOs on the angiogenesis of human umbilical vein endothelial cells (HUVECs) after oxygen and glucose deprivation (OGD). The angiogenesis of microvascular endothelial cells (MECs) in the cortex was tested in neonatal mice treated with hAFEXOs or phosphate-buffered saline (PBS) after hypoxia. Expressions of hypoxia-inducible factor 1 α (HIF-1α) and vascular endothelial growth factor (VEGF) in the cerebral cortex were also tested by western blot. The Morris Water Maze Test (MWM) was carried out to detect the performance of spatial memory after processing with hAFEXOs or PBS. The results indicated that hAFEXOs favored tubing formation and migration of HUVECs after in vitro OGD. The hAFEXOs also favored the expression of CD31 in neonatal mice following hypoxia. The expressions of both HIF-1α and VEGF were significantly augmented in the cerebral cortex of neonatal mice which were treated with hAFEXOs. Moreover, the MWM test results showed that the performance of the spatial memory was better in the hAFEXO-treated group than in the PBS-treated group. Our study indicates that hAFEXOs alleviated hypoxic encephalopathy and enhanced angiogenesis in neonatal mice after hypoxia. In addition, hAFEXOs  promoted migration and tube formation of HUVECs after OGD in vitro. These findings confirm that hAFEXOs show great potential for further studies aimed at developing therapeutic agents for hypoxic encephalopathy.

Design, synthesis and biological activities of benzo[d]imidazo[1,2-a]imidazole derivatives as TRPM2-specfic inhibitors

Transient receptor potential melastatin 2 (TRPM2) channel is associated with ischemia/reperfusion injury, inflammation, cancer and neurodegenerative diseases. However, the lack of specific inhibitors impedes the development of TRPM2 targeted therapeutic agents. To develop a selective TRPM2 inhibitor, three-dimensional similarity-based screening strategy was employed using the energy-minimized conformation of non-selective TRPM2 inhibitor 2-APB as the query structure, which resulted in the discovery of a novel tricyclic TRPM2 inhibitor Z-4 with benzo[d]imidazo[1,2-a]imidazole skeleton. A series of Z-4 derivatives were subsequently synthesized and evaluated using calcium imaging and electrophysiology approaches. Among them, preferred compounds ZA10 and ZA18 inhibited the TRPM2 channel with micromolar half-maximal inhibitory concentration values and exhibited TRPM2 selectivity over the TRPM8 channel, TRPV1 channel, InsP₃ receptor and Orai channel. The analysis of structure-activity relationship provides valuable insights for further development of selective TRPM2 inhibitors. Neuroprotection assay showed that ZA10 and ZA18 could effectively reduce the mortality of SH-SY5Y cells induced by H₂O₂. These findings enrich the structure types of existing TRPM2 inhibitors and might provide a new tool for the study of TRPM2 function in Reactive oxygen species (ROS) -related diseases.

Ceramic Inlay Bonded Interfaces in Minimally Invasive Preparations: Damage and Contributing Mechanisms in Sliding Contact

BACKGROUND

In the preparation of inlay cavities, a choice must be made between conventional standard and minimally invasive preparation designs; in the long run, this choice can affect the integrity of the bonded interface.

PURPOSE

To evaluate the effect of minimally invasive cavity preparation designs on the extent and contributing mechanisms of damage to ceramic inlay bonded interfaces.

METHODS AND MATERIALS

Tooth blocks with 90°, 120° and 75° marginal angles were prepared, representing tooth cavities with conventional standard and minimally invasive preparations with large divergence and convergence angles and bonded to monolithic ceramic (IPS e.max CAD). Vickers indentations were placed at various distances from the bonded interface. The indentation morphology and crack length were observed. Reciprocating wear tests were performed on the bonded interface with a 20-newton (N) vertical load. The wear depth and wear-scar morphology were characterized after increments of cyclic sliding contact.

RESULTS

The 120° group exhibited longer indentation cracks in the ceramic, whereas the 75° group showed larger indentations in the enamel when compared to the 90° group (p<0.001). Consistent with the weaker edge crack resistance, the 120° group experienced the greatest wear (p=0.008), and the wear depth in the enamel of the 75° group exceeded that of the 90° group (p<0.001) in the early stage (5×102 cycles). However, no significant difference in the wear depth (p>0.147) and morphology were found at the later wear stage among the three groups.

CONCLUSION

Within the limitations of this study, minimally invasive preparations with 120° and 75° marginal angles can result in early sever damage at the ceramic inlay bonded interface but show comparable wear behaviors to the conventional 90° group at the later stage.

PSXIII-12 Exploring nutritional differences of canola seeds and bio-processing co-products (meals, pellets) from different processing plants/companies in Canada and China for dairy cattle

Canola was created as a low erucic acid and low glucosinolate seed, to produce high quality oil for human consumption and meal for use in livestock feed. China is an important user of Canadian canola products (seeds, oil, and meal). The extraction of the oil from the seed produces a co-product called canola meal. This meal is rich in protein and is used as a protein source in animal diets. However, differences in the characteristics of the seeds, or processing methods during oil extraction may affect the quality of this co-product. Plus, the synthesis of tissues and milk is related to the amino acids available to the animal for absorption in the small intestine. This study aimed to determine if there are significant differences in the intestinal digestibility (in vitro) of CP and DM between canola seeds and meals from different companies in Canada and to determine if there are significant differences between them in Canada and China. The three-step procedure was applied on residues from a 12-hour rumen incubation in fistulated dairy cows to estimate the intestinal digestibility of CP and DM. There were significant differences (P &lt; 0.05) for TDDM (Total digestible dry matter) and IDP (intestinal digestibility of protein) of the meals between countries. The samples from China had higher TDDM (83.76% versus 81.53%, P = 0.018), while Canada’s had higher IDP (68.51% versus 65.28%, P = 0.016). No significant differences were observed within countries. Based on the material analyzed during this study, it is safe to affirm that there are no significant differences in the digestibility of DM and CP between Canada and China. It was concluded that the quality of the canola seeds or meals produced in both Canada and China were similar when used in dairy rations.

Key words: canola seeds and bio-processing co-products (meals, pellets), nutritional differences, dairy cows

PSXVI-26 Using synchrotron/globar techniques to reveal synergistic and interactive association between molecular structures and nutrient supply in enzymatic and thermal treated oat tissue and whole grain

As an advanced technique, synchrotron radiation-based microspectroscopy SR-FTIRM has been a rapid, direct, non-destructive and non-invasive bioanalytical method. Globar molecular spectroscopic technique -attenuated total reflectance-ATR-FTIR spectroscopy will be used. For this research, feed type CDC Nasser, forage type CDC haymaker, and milling types CDC Arborg and Summit with three consecutive years are studied. There are three treatments for oat samples: Treatment 1, steam pressure processing alone; Treatment 2, adding innovative fibrolytic enzyme; Treatment 3, steam pressure processing plus fibrolytic enzyme. Each treatment combination has three replications. The objectives of this research are to detect the molecular structure spectral features of processed oat endosperm tissues at a molecular and cellular level in relation to chemical profiles, protein and carbohydrate fractions, energy profiles, degradation kinetics, intestinal digestibility, microbial protein production and true nutrient supply of whole oat grains. This research reveals the interactive association between induced molecular structure changes and nutrient properties and true nutrient supply. This research is also to increase economic returns to oat producers and related dairy industries through efficient utilization of feed-type or milling type of oat grains.

PSXIII-1 Effect of varieties and processing methods on physicochemical, nutritional, molecular structural characteristics of feed chickpeas

The objectives of this study were to evaluate the effect of varieties and heat processing methods on molecular structural, physicochemical, and nutritional characterization of feed chickpeas; evaluate the effect of heat processing methods, dry heat, wet heat and microwave irradiation processing method on feed chickpeas as an alternative source for protein and energy feed for ruminant livestock. To reveal the molecular structure spectral profile of chickpeas varieties and the molecular structure changes when applied heat processing methods, vibrational molecular spectroscopy was applied. Feed chickpea samples were determined for chemical profile, energy values, carbohydrate fractions. Subsequently, chickpea samples were incubated in the rumen of dairy cows for degradation kinetics analysis of nutrients. The intestinal digestion of feed chickpea samples was determined using three-step in vitro method with pre-incubation at 16h. Later, protein and carbohydrate related molecular spectral features before and after incubation were performed using vibrational ATR-FTIR molecular spectroscopy. The interactive relationship between processing induced molecular spectral profile changes and nutrient metabolism and availability were studied. The available results showed that varieties and heat processing methods significantly impacted molecular structural, physicochemical, and nutritional characterization of feed chickpeas.

Three-dimensional reconstruction using variable exponential function regularization for wide-field polarization modulation imaging of surface texture of particles

Shapes from the diffuse polarization method effectively realize the three-dimensional (3D) reconstruction of the object surface by using the polarization information of the diffuse reflection light. However, due to the nonconvexity of the particle surface, the reconstruction often falls into a local optimal solution. Indeed, the depth image obtained by the scanning electron microscope has serious stripe noise, which distorts the surface texture of the particle. In this Letter, a variable exponential function regularization method is proposed to realize 3D reconstruction for the nonconvexity of the surface and inclination of the particles. We focus on the gradient unintegrability caused by the skew and surface undulation of the specimen. An adaptive 3D reconstruction method is proposed based on variable exponential function regularization to fit the surface function of the particle. Experimental results of finite-difference time-domain simulations and actual imaging demonstrate the effectiveness of the method.

[Prediction of the vaulting after posterior chamber intraocular lens implantation]

Objective: To investigate the influencing factors on the vaulting one month after implantable collamer lens (ICL) implantation, and to develop and verify a prediction formula. Methods: The first half of this study was retrospective case series study, and the second half was cross-sectional stydy. A total of 83 eyes of 83 patients who underwent ICL implantation in the Lixiang Eye Hospital of Soochow University were included in the first half of the study, with an average age of (27±5) years, from August 1, 2019 to December 30, 2019. All patients underwent a complete preoperative examination, including axis length, anterior chamber depth, comprehensive optometry, intraocular pressure, central corneal thickness, white-to-white diameter, horizontal and vertical sulcus-to-sulcus diameter (STS), crystalline lens thickness (LT), corneal curvature, and bright and dark pupil diameter. Multiple linear regression (stepwise) was used to develop a prediction formula. In the validation part, a total of 65 people (65 eyes) were included, with an average age of (26±5) years, from March 1, 2020 to June 1, 2020. The accuracy and reliability of the formula were verified by the intergroup correlation coefficient and Bland-Altman consistency test. Results: At 1 month after surgery, ICL size had the greatest impact on the vaulting (β=0.942, P<0.001), followed by horizontal STS (β=-0.517, P<0.001), LT (β=-0.376, P<0.001), and vertical STS (β=-0.257, P=0.017). The influence of other factors was not statistically significant (all P>0.05). The regression equation was as follows: the vaulting (μm)=-1 369.05+657.12×ICL size-287.41×horizontal STS-432.50×LT-137.33×vertical STS (the fitting degree R=0.813, R²=0.660, and corrected R²=0.643). In the verification part, the predicted average vaulting was (497.31±102.75) μm, while the actual vaulting was (514.62±152.99) μm. About 96.92% (63/65) of the patients were fitted in the moderate vault, and 3.08% (2/65) were in the high vault. The intergroup correlation coefficient was 0.581. According to the Bland-Altman test, the actual vaulting was 17.31 μm, higher than the predicted value, and the 95% confidence interval of the difference was -260.28 to 294.90 μm. Conclusion: The ICL size, horizontal and vertical STS and LT are the factors that affect and predict the vaulting one month after ICL implantation, and our prediction formula has good accuracy and reliability. (Chin J Ophthalmol, 2021, 57: 519-525).

Study of PWR hot leg creep rupture and RCS depressurization strategy during an SBO accident

Preventing the leakage of radioactive materials is important to nuclear safety. During a station blackout accident in pressurized water reactors, the hot leg creep rupture caused by hot leg countercurrent flow occurs before the reactor pressure vessel failure that caused by lower head rupture. The secondary fission products barrier is lost after hot leg creep rupture. An analysis for this phenomenon was done using the Modular Accident Analysis Program version 4.0.4 code. A station blackout accident for CPR1000 is simulated and the occurrence and influence of hot leg creep rupture phenomenon are analyzed in detail. After that, a sensitivity analysis of the opening of different pressurizer pilot-operated relief valves at five minutes after entering severe accident management guideline (before the hot leg creep rupture occurs) is studied. The results show that reactor pressure vessel failure time can be extended by at least 4 h if at least one pilot-operated relief valve is opened and direct containment heating phenomenon can be eliminated if at least two pilot-operated relief valves are opened.

The Discovery of Novel ACA Derivatives as Specific TRPM2 Inhibitors that Reduce Ischemic Injury Both In Vitro and In Vivo

The transient receptor potential melastatin 2 (TRPM2) channel is associated with ischemia/reperfusion injury, inflammation, cancer, and neurodegenerative diseases. However, the limit of specific inhibitors impedes the development of TRPM2-targeted therapeutic agents. To discover more potent and selective TRPM2 inhibitors, 59 N-(p-amylcinnamoyl) anthranilic acid (ACA) derivatives were synthesized and evaluated using calcium imaging and electrophysiology approaches. Systematic structure-activity relationship studies resulted in some potent compounds inhibiting the TRPM2 channel with sub-micromolar half-maximal inhibitory concentration values. Among them, the preferred compound A23 exhibited TRPM2 selectivity over TRPM8 and TRPV1 channels as well as phospholipase A2 and showed neuroprotective activity in vitro. Following pharmacokinetic studies, A23 was further evaluated in a transient middle cerebral artery occlusion model in vivo, which significantly reduced cerebral infarction. These data indicate that A23 might serve as a useful tool for TRPM2-related research as well as a lead compound for the development of therapeutic agents for ischemic injury.

[Cone-beam CT evaluation of the Monson's spherical radius of young adults in Guangdong]

Objective: To measure and analyze the spherical radius of Monson of normal young people in Guangdong province using cone-beam CT (CBCT), and to establish a personalized measurement method of the spherical radius of Monson to provide a reference for clinical application of Monson spherical radius in occlusal reconstruction. Methods: Sixty healthy young adults from physical examination population at Stomatology Hospital of Guangzhou Medical University [30 males and 30 females, aged (22.1±2.0) years 18-26 years) were recruited, and their CBCT were taken. Three-dimensional reconstruction of CBCT data was carried out, and the reconstructed models were fixed, traced and measured. The difference of Monson spherical radius between male and female was compared by using a single sample t-test. Results: The Monson spherical radius was (100.72±4.89) mm. The Monson spherical radius of male and female were (103.48±4.19) mm and (97.97±3.93) mm respectively. The difference between male and female was statistically significant (P<0.01). Conclusions: CBCT can be used to accurately measure the spherical radius of Monson and can be used as a reference for reconstruction of occlusal plane.

[Prevalence of CYP2C19 gene mutations in patients with coronary heart disease and its biological activation effect in clopidogrel antiplatelet response]

Objective: The purpose of this study was to investigate the effects of CYP2C19 gene mutations on clopidogrel antiplatelet activity in the patients with coronary heart disease treated by percutaneous coronary intervention. Methods: Patients with coronary heart disease, who hospitalized in the Second Affiliated Hospital of Nanchang University from March 2011 to June 2019, and healthy individuals with matching genetic background, gender, and age as controls were included in this study. Basic clinical data were analyzed and blood samples of all research subjects were obtained for extraction of DNA, and Sanger first-generation sequencing method was used to detect CYP2C19 gene mutation from full exon and exon and intron junction. CYP2C19 gene variations in patients with coronary heart disease were compared with the 1000 Genomes Browse database and the sequencing results of healthy controls to determine whether the gene variation was a genetic mutation or a genetic polymorphism. After that, PolyPhen-2 prediction software was used to analyze the harmfulness of gene mutations to predict the effect of mutations on protein function. The same dose of CYP2C19 wild-type plasmid and the CYP2C19 gene mutant plasmids were transfected into human normal liver cells HL-7702. After transfection of 24 h, the expression of CYP2C19 protease in each group was detected. The liver S9 protein was incubated with clopidogrel, acted on platelets to detect the platelet aggregation rate and the activity of human vasodilator-activated phosphoprotein (VASP). Results: A total of 1 493 patients with coronary heart disease (59.36%) were enrolled, the average age was (64.5±10.4) years old, of which 1 129 were male (75.62%). Meanwhile, 1 022 healthy physical examination volunteers (40.64%) were enrolled, and the average age was (64.1±11.0) years old, of which 778 were male (76.13%). A total of 5 gene mutations of CYP2C19 gene were identified in 12 patients (0.80%), namely, 4 known mutations T130K (1 case), M136K (6 cases), N277K (3 cases), V472I (1 case) and one new mutation G27V (1 case), no corresponding gene mutation was found in healthy controls. It was found that T130K and M136K were probably damaging, G27V was possibly damaging, and N277K and V472I were benign mutations. In vitro, we demonstrated that the platelet aggregation rate of the M136K gene mutation group was 24.83% lower than that of the wild type (59.58% vs. 34.75%; P<0.05), and the phosphorylated VASP level was 23.0% higher than that of the wild type (1.0 vs. 1.23; P<0.05). However, the platelet aggregation rate and phosphorylated VASP level were similar between of G27V, T130K, N277K, V472I gene mutation groups and wild type group (P>0.05). Conclusions: In this study, 5 gene mutations are defined in patients with coronary heart disease, namely G27V, T130K, M136K, N277K, V472I. In vitro functional studies show that CYP2C19 gene mutation M136K, as a gain-of-function gene mutation, can enhance the activation of CYP2C19 enzyme on clopidogrel, thereby inhibiting the platelet aggregation rate.