Influence of electronic correlation on the valley and topological properties of VSiGeP4 monolayer

Valley is used as a new degree of freedom for information encoding and storage. In this work, the valley and topological properties of the VSiGeP4 monolayer were studied by adjusting the U value based on first-principles calculations. The VSiGeP4 monolayer remains in a ferromagnetic ground state regardless of the change in the U value. The magnetic anisotropy of the VSiGeP4 monolayer is initially in-plane, and then turns out-of-plane with the increase in the U value. Moreover, a topological phase transition is observed in the present VSiGeP4 monolayer with the increase in U value from 0 to 3 eV, i.e., the VSiGeP4 monolayer behaves as a bipolar magnetic semiconductor, a ferrovalley semiconductor, a half-valley metal characteristic, and a quantum anomalous Hall state. The mechanism of the topological phase transition behavior of the VSiGeP4 monolayer was analyzed. It was found that the variation in U values would change the strength of the electronic correlation effect, resulting in the valley and topological properties. In addition, carrier doping was studied to design a valleytronic device using this VSiGeP4 monolayer. By doping 0.05 electrons per f.u., the VSiGeP4 monolayer with a U value of 3 eV exhibits 100% spin polarization. This study indicates that the VSiGeP4 monolayer has potential applications in spintronic, valleytronic, and topological electronic nanodevices.

First-principles study of high-pressure structural phase transition and superconductivity of YBeH8

The theory-led prediction of LaBeH8, which has a high superconducting critical temperature (Tc) above liquid nitrogen under a pressure level below 1 Mbar, has been experimentally confirmed. YBeH8, which has a structural configuration similar to that of LaBeH8, has also been predicted to be a high-temperature superconductor at high pressure. In this study, we focus on the structural phase transition and superconductivity of YBeH8 under pressure by using first-principles calculations. Except for the known face-centered cubic phase of Fm3̄m, we found a monoclinic phase with P1̄ symmetry. Moreover, the P1̄ phase transforms to the Fm3̄m phase at ∼200 GPa with zero-point energy corrections. Interestingly, the P1̄ phase undergoes a complex electronic phase transition from semiconductor to metal and then to superconducting states with a low Tc of 40 K at 200 GPa. The Fm3̄m phase exhibits a high Tc of 201 K at 200 GPa, and its Tc does not change significantly with pressure. When we combine the method using two coupling constants, λopt and λac, with first-principles calculations, λopt is mainly supplied by the Be-H alloy backbone, which accounts for about 85% of total λ and makes the greatest contribution to the high Tc. These insights not only contribute to a deeper understanding of the superconducting behavior of this ternary hydride but may also guide the experimental synthesis of hydrogen-rich compounds.

Twinning Engineering of Platinum/Iridium Nanonets as Turing-Type Catalysts for Efficient Water Splitting

The twin boundary, a common lattice plane of mirror-symmetric crystals, may have high reactivity due to special atomic coordination. However, twinning platinum and iridium nanocatalysts are grand challenges due to the high stacking fault energies that are nearly 1 order of magnitude larger than those of easy-twinning gold and silver. Here, we demonstrate that Turing structuring, realized by selective etching of superthin metal film, provides 14.3 and 18.9 times increases in twin-boundary densities for platinum and iridium nanonets, comparable to the highly twinned silver nanocatalysts. The Turing configurations with abundant low-coordination atoms contribute to the formation of nanotwins and create a large active surface area. Theoretical calculations reveal that the specific atom arrangement on the twin boundary changes the electronic structure and reduces the energy barrier of water dissociation. The optimal Turing-type platinum nanonets demonstrated excellent hydrogen-evolution-reaction performance with a 25.6 mV overpotential at 10.0 mA·cm-2 and a 14.8-fold increase in mass activity. And the bifunctional Turing iridium catalysts integrated in the water electrolyzer had a mass activity 23.0 times that of commercial iridium catalysts. This work opens a new avenue for nanocrystal twinning as a facile paradigm for designing high-performance nanocatalysts.

Superconductivity of cubic MB6 (M = Na, K, Rb, Cs)

Previous studies have shown that NaB6, KB6, and RbB6 adopting Pm3̄m are superconductors with a relatively high Tc under ambient conditions. In this paper, we conducted systematic structural and related properties research on CsB6 through a genetic evolution algorithm and total energy calculations based on density functional theory between 0 and 20 GPa. Our results reveal a cubic Pm3̄m CsB6, which is dynamically stable under the pressures we studied. We systematically calculated the formation enthalpies, electronic properties, and superconducting properties of Pm3̄m MB6 (M = Na, K, Rb, Cs). They all exhibit metallic features, and boron has high contributions to band structures, density of states, and electron-phonon coupling (EPC). The calculated results about the Helmholtz free energy difference of Pm3̄m CsB6 at 0, 10, and 20 GPa indicate that it is stable upon chemical decomposition (decomposition to simple substances Cs and B) from 0 to 400 K. The phonon density of states indicates that boron atoms occupy the high frequency area. The EPC results show that Pm3̄m CsB6 is a superconductor with Tc = 11.7 K at 0 GPa, close to NaB6 (13.1 K), KB6 (11.7 K), and RbB6 (11.3 K) at 0 GPa in our work, which indicates that boron atoms play an essential role in superconductivity: vibrations of B6 regular octagons lead to the high Tc of Pm3̄m MB6. Our work about Pm3̄m hexaborides provides a supplementary study on the borides of the group IA elements (without Fr and Li) and has an important guiding significance for the experimental synthesis of CsB6.

Remnant cholesterol is associated with hip BMD and low bone mass in young and middle-aged men: a cross-sectional study

PURPOSE

Remnant cholesterol (RC) is a contributor to cardiovascular diseases, obesity, diabetes, and metabolic syndrome. However, the specific relationship between RC and bone metabolism remains unexplored. Therefore, we aimed to investigate the relationships of RC with hip bone mineral density (BMD) and the risk of low bone mass.

METHODS

Physical examination data was collected from men aged < 60 years as part of the Kailuan Study between 2014 and 2018. The characteristics of the participants were compared between RC quartile groups. A generalized linear regression model was used to evaluate the relationship between RC and hip BMD and a logistic regression model was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for low bone mass. Additional analyses were performed after stratification by body mass index (BMI) (≥ or < 24 kg/m2). Sensitivity analyses were performed by excluding individuals who were taking lipid-lowering therapy or had cancer, cardiovascular diseases, or diabetes.

RESULTS

Data from a total of 7,053 participants were included in the analysis. After adjustment for confounding factors, RC negatively correlated with hip BMD (β =  - 0.0079, 95% CI: - 0.0133, - 0.0025). The risk of low bone mass increased from the lowest to the highest RC quartile, with ORs of 1 (reference), 1.09 (95% CI: (0.82, 1.44), 1.35 (95%CI: 1.02, 1.77), and 1.43 (95% CI: 1.09, 1.89) for Q1, Q2, Q3, and Q4, respectively (P for trend = 0.004) in the fully adjusted model. Compared to RC < 0.80 mmol/l group, the risk of low bone mass increased 39% in RC ≥ 0.80 mmol/l group (P < 0.001). The correlation between RC and hip BMD was stronger in participants with BMI ≥ 24 kg/m2 group (β =  - 0.0159, 95% CI: - 0.0289, - 0.0029). The results of sensitivity analyses were consistent with the main results.

CONCLUSION

We have identified a negative correlation between serum RC and hip BMD, and a higher RC concentration was found to be associated with a greater risk of low bone mass in young and middle-aged men.

Measurement of oesophageal hiatus surface area by multiplanar reconstruction of MDCT: relationship with lower oesophageal sphincter pressure and acid reflux

AIM

To evaluate the relationship between oesophageal hiatus surface area (OHSA) and gastro-oesophageal reflux disease (GERD).

MATERIALS AND METHODS

Patients who underwent 24-h pH monitoring, oesophageal high-resolution manometry, and upper abdominal contrast-enhanced multidetector computed tomography (MDCT) during 2014-2021 were enrolled. Patients with a hiatus hernia (HH) on MDCT or who had a history of gastro-oesophageal surgery were excluded. Multiplanar reconstruction (MPR) of the MDCT image was used for the measurement of OHSA. Correlations of OHSA with acid exposure time (AET) and lower oesophageal sphincter (LOS) pressure of all patients were analysed.

RESULTS

Seventy-eight patients were included in the study. OHSA was much less in the AET <4% group than in the AET >6% group (1.61 ± 0.42 versus 2.09 ± 0.55 cm2, p<0.001). Correlation analysis reveals that OHSA correlated positively with AET (correlation coefficient = 0.47, p<0.001). Receiver operating characteristic (ROC) curve analysis reveals that OHSA can significantly distinguish patients in different groups divided by AET (area under the ROC curve [AUC] = 0.76, 95% confidence interval [CI]: 0.63-0.90). OHSA was not related to LOS pressure (correlation coefficient = -0.268, p=0.051). There was no difference in OHSA between the low LOS pressure group and the normal LOS pressure group (1.84 ± 0.61 versus 1.74 ± 0.50 cm2, p=0.52).

CONCLUSIONS

OHSA significantly correlated with AET but has no relationship with LOS pressure. It may be an independent risk factor of GERD.

Turing structuring with multiple nanotwins to engineer efficient and stable catalysts for hydrogen evolution reaction

Low-dimensional nanocrystals with controllable defects or strain modifications are newly emerging active electrocatalysts for hydrogen-energy conversion and utilization; however, a crucial challenge remains in insufficient stability due to spontaneous structural degradation and strain relaxation. Here we report a Turing structuring strategy to activate and stabilize superthin metal nanosheets by incorporating high-density nanotwins. Turing configuration, realized by constrained orientation attachment of nanograins, yields intrinsically stable nanotwin network and straining effects, which synergistically reduce the energy barrier of water dissociation and optimize the hydrogen adsorption free energy for hydrogen evolution reaction. Turing PtNiNb nanocatalyst achieves 23.5 and 3.1 times increase in mass activity and stability index, respectively, compared against commercial 20% Pt/C. The Turing PtNiNb-based anion-exchange-membrane water electrolyser with a low Pt mass loading of 0.05 mg cm-2 demonstrates at least 500 h stability at 1000 mA cm-2, disclosing the stable catalysis. Besides, this new paradigm can be extended to Ir/Pd/Ag-based nanocatalysts, illustrating the universality of Turing-type catalysts.

Coexisting Ferroelectric and Ferrovalley Polarizations in Bilayer Stacked Magnetic Semiconductors

It has long been expected that the coexistence of ferroelectric and ferrovalley polarizations in one magnetic semiconductor could offer the possibility to revolutionize electronic devices. In this study, monolayer and bilayer YI₂ are studied. Monolayer YI₂ is a ferromagnetic semiconductor and exhibits a valley polarization up to 105 meV. All of the present bilayer YI₂ regardless of stacking orders show antiferromagnetic states. Interestingly, the bilayer YI₂ with 3R-type stackings shows not only valley polarization but also unexpected ferroelectric polarization, proving the concurrent ferrovalley and multiferroics behaviors. Moreover, the valley polarization of 3R-type bilayer YI₂ can be reversed by controlling the direction of ferroelectric polarization through an electric field or manipulating the magnetization direction using an external magnetic field. The amazing phenomenon is also demonstrated in 2D van der Waals LaI₂ and GdBr₂ bilayers. A design idea of multifunctional devices is proposed based on the concurrent ferrovalley and multiferroics characteristics.

Distinct ferrovalley characteristics of the Janus RuClX (X = F, Br) monolayer

Two-dimensional ferrovalley materials should simultaneously possess three characteristics, that is, a Curie temperature beyond atmospheric temperature, perpendicular magnetic anisotropy, and large valley polarization for potential commercial applications. In this report, we predict two ferrovalley Janus RuClX (X = F, Br) monolayers by first-principles calculations and Monte Carlo simulations. The RuClF monolayer exhibited a valley-splitting energy as large as 194 meV, perpendicular magnetic anisotropy energy of 187 μeV per f.u., and Curie temperature of 320 K. Thus, spontaneous valley polarization at room temperature will be present in the RuClF monolayer, which is nonvolatile for spintronic and valleytronic devices. Although the valley-splitting energy of the RuClBr monolayer was as high as 226 meV with magnetic anisotropy energy of 1.852 meV per f.u., the magnetic anisotropy of the RuClBr monolayer was in-plane, and its Curie temperature was only 179 K. The orbital-resolved magnetic anisotropy energy revealed that the interaction between the occupied spin-up states of d_yz and the unoccupied spin-down states of d_z² dominated the out-of-plane magnetic anisotropy in the RuClF monolayer, but the in-plane magnetic anisotropy of the RuClBr monolayer was mostly contributed by the coupling of the d_xy and d_x²-y² orbitals. Interestingly, the valley polarizations in the Janus RuClF and RuClBr monolayers appeared in their valence band and conduction band, respectively. Thus, two anomalous valley Hall devices are proposed using the present Janus RuClF and RuClBr monolayers with hole and electron doping, respectively. This study provides interesting and alternative candidate materials for the development of valleytronic devices.

Effect of Shenqi millet porridge on gastrointestinal function decline

OBJECTIVE

To explore the effect of Shenqi millet porridge on treating gastrointestinal function decline.

METHODS

Clinical data of 72 patients with gastrointestinal function decline were retrospectively analyzed. Patients were divided into an observation group (n=36, treated with Shenqi millet porridge) and a control group (n=36, treated with Changweikang granule) according to the treatment methods. The therapeutic effect, quality of life, nutritional status, and levels of motilin and gastrin were analyzed.

RESULTS

The total response rate of the observation group was significantly higher than that of the control group (97.22% vs. 72.22%; P<0.05). Compared with the control group, the quality of life in the observation group was increased after treatment (all P<0.05), and the total protein and body mass index in the observation group were higher than those in the control group (all P<0.05), while the levels of motilin and gastrin in the observation group were lower than those in the control group (all P<0.05).

CONCLUSION

For patients with gastrointestinal function decline, the therapeutic regimen Shenqi millet porridge ameliorates the nutritional status of patients, as well as the quality of life and total therapeutic efficacy, also reduces the levels of motilin and gastrin. This regimen has high safety and clinical application value.

[Correlation between polycyclic aromatic hydrocarbons component phenanthrene and clinical indicators in patients on peritoneal dialysis]

Objective: To explore the correlation between polycyclic aromatic hydrocarbons (PAHs) component phenanthrene and clinical indicators in patients on continuous ambulatory peritoneal dialysis (CAPD). Methods: A total of 22 patients who underwent peritoneal dialysis catheterization and regular dialysis in the First Affiliated Hospital of Zhengzhou University from June to August 2018 were selected. Meanwhile, 18 healthy adults who underwent physical examination were also selected as the control group. Fasting blood samples were taken to detect the concentration of PAHs components for comparison, and the correlation between PAHs components and clinical indicators was further analyzed. Results: There were 22 cases in CAPD group (13 males and 9 females), and aged (45±13) years, while there were 18 cases in control group (6 males and 12 females), and aged (41±13) years. The concentration of blood phenanthrene (PHE) was the highest in CAPD group [0.449 (0.254, 0.581) mg/L], and it was only lower than acenaphthene in the control group [0.081 (0.050, 0.444) mg/L], with a statistically significant difference between the two groups (P=0.008). The analysis of PHE and clinical indicators showed that the concentration of PHE in CAPD patients was negatively correlated with weekly urea clearance index (Kt/V), weekly creatinine clearance (Ccr) and leukocyte level, but positively correlated with triglyceride level (r=-0.743, -0.749, -0.655 and 0.610, respectively, all P<0.05). Simple linear regression analysis demonstrated that for every 0.1 mg/L increase in PHE concentration, weekly Kt/V, weekly Ccr and white blood cell count decreased by 0.226, 3.050 L/1.73 m² and 0.512×10⁹/L, respectively, but triglyceride level increased by 0.152 mmol/L (all P<0.05). Multiple linear regression analysis revealed that the blood PHE concentration of CAPD patients was negatively correlated with weekly Kt/V and Ccr levels (t=-2.402 and -2.368, respectively, both P<0.05). All CAPD patients were followed up for 3 years, during which 8 patients (36.4%) withdrew from peritoneal dialysis due to technical failure, and the baseline PHE concentration was higher than that of patients who did not quit peritoneal dialysis [0.572 (0.416, 0.662) vs 0.268 (0.120, 0.475) mg/L, P=0.003]. Eight patients (36.4%) had cardiovascular events, and the baseline blood PHE concentration was higher than that of patients without cardiovascular events [0.542 (0.389, 0.741) vs 0.373 (0.157, 0.545) mg/L, P=0.045]. Conclusion: PHE correlates with clinical indicators of CAPD patients, including Kt/v, Ccr, leukocyte and triglyceride.

First principle studies of TiO2-ZnO alloys under high pressure

The ZnO-TiO₂composite system has been applied as a photocatalyst in the treatment of organic waste and domestic wastewater due to its high separation rate of photogenerated carriers and wide light response range. Using the first-principles approach based on density functional theory, we investigated the crystal structures and the electronic properties of ZnO-TiO₂alloys under high pressure and predicted three stable high-pressure phases (CmcmZnTiO₃,ImmaZn₂TiO₄andCmZnTi₃O₇). Calculations of the phonon spectra and elastic constants showed that the predicted structures are dynamically and mechanically stable. In terms of electronic properties, it was found that the three crystal structures were all semiconductors. With the increase of pressure, the band gap ofCmZnTi₃O₇showed an increasing trend, while the band gap ofCmcmZnTiO₃andImmaZn₂TiO₄gradually decreased. The calculated band structures showed that the band gap first increases nonlinearly and then decreases as the Zn concentration increases. Pressure can regulate the band gap of the above crystals, making them promising for applications in photocatalysis and microwave devices.

Lactation time influences the composition of Bifidobacterium and Lactobacillus at species level in human breast milk

Human breast milk is a source of microorganisms for infants that play an important role in building infant gut health and immunity. The bacterial composition in human breast milk is influenced by lactation time. This study aimed to investigate the influence of lactation time on bacteria in breast milk at the genus level and the species levels of Bifidobacterium and Lactobacillus on days 2-4, 8, 14, and 30. Eighteen individuals were recruited and 60 milk samples were collected. The 16S rRNA gene, and the bifidobacterial groEL and lactobacilli groEL genes were used for amplicon sequencing. The results revealed that the alpha diversities of colostrum and transition 1 (day 8) milk were lower than that of transition 2 (day 14) and mature milk. PCoA analysis showed that bacterial composition in colostrum and transition 1 milk differed from transition 2 and mature milk. A lower relative abundance of Blautia was found in colostrum and transition 1 milk compared with mature milk and lower abundances of Ruminococcus, Dorea, and Escherichia-Shigella were found in transition 1 compared with mature milk. Bifidobacterium ruminantium, Limosilactobacillus mucosae, and Ligilactobacillus ruminis were the predominant species across all four lactation stages, while Bifidobacterium bifidum was lower in transition 1, and Bifidobacterium pseudocatenulatum and Bifidobacterium pseudolongum were higher in transition 1 milk. This study indicated that the bacterial composition in colostrum was more similar to that of transition 1 milk, whereas the bacterial community in transition 2 milk was similar to that of mature milk which suggests that bacterial composition in human breast milk shows stage-specific signatures even within a short period at both genus level and Bifidobacterium and Lactobacillus species levels, providing insights into probiotic supplementation for the nursing mother.

Structural diversity and hydrogen storage properties in the system K-Si-H

KSiH₃ exhibits 4.1 wt% experimental hydrogen storage capacity and shows reversibility under moderate conditions, which provides fresh impetus to the search for other complex hydrides in the K-Si-H system. Here, we reproduce the stable Fm3̄m phase of K₂SiH₆ and uncover two denser phases, space groups P3̄m1 and P6₃mc at ambient pressure, by means of first-principles structure searches. We note that P3̄m1-K₂SiH₆ has a high hydrogen content of 5.4 wt% and a volumetric density of 88.3 g L^-1. Further calculations suggest a favorable dehydrogenation temperature T_des of -20.1/55.8 °C with decomposition into KSi + K + H₂. The higher hydrogen density and appropriate dehydrogenation temperature indicate that K₂SiH₆ is a promising hydrogen storage material, and our results provide helpful and clear guidance for further experimental studies. We found three further potential hydrogen storage materials stable at high pressure: K₂SiH₈, KSiH₇ and KSiH₈. These results suggest the need for further investigations into hydrogen storage materials among such ternary hydrides at high pressure.

Ropivacaine with intraspinal administration alleviates preeclampsia-induced kidney injury via glycocalyx /alpha 7 nicotinic acetylcholine receptor pathway

Preeclampsia is characterized by hypertension and proteinuria, which is associated with kidney injury. Glycocalyx (GCX) degradation mediated endothelial injury can result in proteinuria and kidney damage. alpha 7 nicotinic acetylcholine receptor (α7nAChR) connects nervous and immune systems to respond to stress or injury. We aimed to explore the protective effect and mechanism of intraspinal analgesia on maternal kidney injury in preeclampsia. Endotoxin-induced preeclampsia rats treated with ropivacaine via intraspinal administration. Renal histopathological examination was performed, cell apoptosis in the kidney, the levels of Glycocalyx markers of Syndecan-1 and heparin sulfate (HS) in maternal serum, Syndecan-1 along with α7nAChR in the kidney were measured. Our results showed that kidney injury was obviously in preeclampsia rats with proteinuria, endothelial damage, higher apoptosis rate, increasing levels of Syndecan-1 and HS in serum, upregulated Syndecan-1 expression but downregulated α7nAChR expression in kidney. Preeclampsia rats treated with intraspinal injected ropivacaine attenuated preeclampsia-induced kidney injury as Syndecan-1 and HS were decreased in serum, Syndecan-1 expression was suppressed as well as α7nAChR was activated in the kidney. Our results suggested that Ropivacaine administered through the spinal canal may protect preeclampsia-induced renal injury by decreasing GCX and α7nAChR activation.

Studies on microRNA regulation of multidirectional differentiation of dental pulp stem cells: a narrative review

OBJECTIVE

Dental pulp stem cells (DPSCs) are adult stem cells of neural crest origin, are readily available, have good self-renewal and multidirectional differentiation properties, can differentiate into a variety of cells, are abundant, less harmful to donate, have no ethical issues, low immunogenicity, and therefore, are widely used as seed cells in the field of tissue engineering and regenerative medicine. MicroRNA (miRNA) is a single-stranded non-coding small RNA consisting of about 22 nucleotides, which plays an important regulatory role in various aspects of cellular activities, such as proliferation, differentiation, and apoptosis. In this paper, we review the regulatory role of small RNA in the differentiation of DPSCs and its mechanism in the past 5 years. This paper aims to reveal the important role of miRNAs in differentiation in DPSCs.

MATERIALS AND METHODS

MicroRNAs (miRNAs), differentiation, and DPSCs were extensively searched in three databases from 2014 to 2021. These databases include PubMed, Cochrane Library, Embase.

RESULTS

Our study reviews the microRNAs (miR-145, miR-143-3p, miR-140-5p, miR-488, miR-218, miR-125a-3p, miR-27a-5p, miR-223, miR-21, miR-143, miR-215, miR-219a-1-3p, miR-31, miR-496, miR-218, miR-24-3p, miR-146a-5p, miR-196a, miR-188-3p, miR-424, miR-378a, miR-135, miR-124) in the differentiation of DPSCs.

CONCLUSIONS

A large body of evidence supports the involvement of miRNAs in differentiation associated with mesenchymal stem cells (MSCs), although the mechanisms involved are not yet clear. Most of the current studies are from in vitro studies, but the ultimate goal is to apply these studies to the clinic, and studies involving in vivo models are needed.

[Mechanism study of the protective effects of selective cyclooxygenase-2 enzyme inhibitors on the liver of rats with type 2 diabetes mellitus combined with nonalcoholic steatohepatitis via Rho/ROCK pathway]

Objective: To investigate whether the selective cyclooxygenase-2 enzyme inhibitors celecoxib has protective effect on the liver of rats with type 2 diabetes mellitus (T2DM) combined with nonalcoholic steatohepatitis (NASH) via inhibiting the expression of Rho/ROCK pathway. Methods: Forty male SD rats were randomly divided into four groups: type 2 diabetes mellitus combined with nonalcoholic steatohepatitis (T2DM-NASH) group, T2DM-NASH + celecoxib group, control group, and control+celecoxib group. The T2DM-NASH and T2DM-NASH + celecoxib groups were fed with high-sugar and fat diet, and the control group and control + celecoxib group were fed with basal diet (25 kJ/kg). Four weeks later, streptozotocin (STZ, 30 mg/kg) was intraperitoneally injected into the NASH group and T2DM-NASH + celecoxib group to induce T2DM model, and the control group and control + celecoxib group were intraperitoneally injected with isovolumic citric acid-sodium citrate buffer. Four weeks after STZ injection, the T2DM-NASH + celecoxib group and the control + celecoxib group were gavaged with celecoxib (10 mg·kg·d) dissolved in normal saline for 4 weeks, and the remaining two groups of rats were gavaged with isovolumic normal saline for 4 weeks. Animals were sacrificed at the end of the 12- weeks, and the liver tissue was collected. Liver pathological changes were observed by HE staining. The expressions of RhoA, RhoA, ROCK1 and ROCK2 proteins in liver were detected by immunohistochemistry and western blot. The expressional condition of RhoA, ROCK1 and ROCK2 mRNA in liver were detected by real-time quantitative PCR. The differences were compared between protein and mRNA expression among the groups by analysis of variance and t-test. Results: Compared with the control group and the control + celecoxib group, the liver tissue of the T2DM-NASH group and the T2DM-NASH + celecoxib group had severe steatosis, and there was partial inflammatory cell infiltration under the light microscope. The expression levels of RhoA, ROCK1 and ROCK2 protein and mRNA were significantly increased (P < 0.05) in each liver tissue, while liver steatosis was reduced to certain extent in T2DM-NASH + celecoxib group than T2DM-NASH group, and the expression levels of RhoA, ROCK1 and ROCK2 protein and mRNA were decreased in each liver tissue of T2DM-NASH group (P < 0.05). Conclusion: The selective cyclooxygenase-2 enzyme inhibitors celecoxib has a protective effect on the liver of rats with T2DM-NASH, and its effect may be achieved by inhibiting the expression of Rho/ROCK pathway.

Research progress of scar repair and its influence on physical and mental health

A scar is a normal and an inevitable physiological response to the natural healing process of wounds or trauma in the human body. The essence of scar is a kind of abnormal and unsound tissue that does not possess the structure, physiological function and vitality of normal skin tissue. Scars not only affect the beauty of the body surface, but also impede the physiological function of the related tissues and organs, and even lead to deformities. Therefore, scar repair is of great significance to patients' appearance, physiological function as well as physical and mental health. Currently, the main approaches for scar repair in clinic are photorejuvenation or fruit acids. The purpose of this study is to investigate the current research progress of scar repair and the impact of scar repair on the physical and mental health of patients.

[Systematic review on the reform of disease prevention and control system in China]

Objective: To systematically understand the reform progress of disease prevention and control system in China. Methods: The literature regarding the reform of China's disease prevention and control system was searched by using the keywords including disease prevention and control, center for disease prevention and control (CDC), disease control, reform, and system from 2003 to 2020 in China CNKI, Wanfang Data knowledge service platform, VIP information and China biomedical literature database. The language is limited to Chinese. A total of 25 studies were included to analyze the information about the organizational structure, functional orientation, financing mechanism and personnel system of China's disease prevention and control system. Results: The 25 studies described the specific changes and reform suggestions of China's disease prevention and control system, including key policies (7 studies), organizational structure transformation (4 studies), institutional function transformation (7 studies), financing mechanism transformation (5 studies), personnel system reform (2 studies), and performance-based salary system reform (4 studies). Meanwhile, the reform suggestions were concluded at the top-level design system reform (two aspects), organization structure (three aspects), functioning (four aspects), and personnel guarantee mechanism (three aspects). Conclusions: This study indicates that there is a lack of empirical evidence regarding specific reform effects and content analysis at the micro level of disease prevention and control system in China. Future study should strengthen the rigorousness of study design and focus on the quantitative impacts of reform implementation in China.

Proposed Superconducting Electride Li_{6}C by sp-Hybridized Cage States at Moderate Pressures

The combination of electride state and superconductivity within the same compound, e.g., [Ca_{24}Al_{28}O_{6}]^{4+}(4e^{-}), opens up a new category of conventional superconductors. However, neither the underlying causations to explain superconducting behaviors nor effects of interstitial quasiatoms (ISQs) on superconductivity remain unclear. Here we have designed an efficient and resource-saving method to identify superconducting electrides only by chemical compositions and bonding characteristics. A representative superconducting electride Li_{6}C with a noteworthy T_{c} of 10 K below 1 Mbar among the known binary electrides has been revealed. Our first-principles studies unveil that the anomalous sp-hybridized cage-state ISQs, as a guest in Li_{6}C, exhibit unexpected ionic and covalent bonds, which act as a chemical precompression to lower dynamically stable pressure. More importantly, we uncover that, contrary to common expectations, the high T_{c} is attributed to the strong electron-phonon coupling derived from the synergy of interatomic coupling effect, phonon softening caused by Fermi surface nesting, and phonon-coupled bands, which are mainly dominated by host sp-hybridized electrons, rather than the ISQs. Our present results elucidate a new superconducting mechanism of electrides and shed light on the way for seeking a high-T_{c} superconductor at lower pressures in cage-state electrides.

Enhanced resistive switching performance in yttrium-doped CH3NH3PbI3 perovskite devices

In this study, yttrium-doped CH₃NH₃PbI₃ (Y-MAPbI₃) and pure CH₃NH₃PbI₃ (MAPbI₃) perovskite films have been fabricated using a one-step solution spin coating method in a glove box. X-ray diffractometry and field-emission scanning electron microscopy were used to characterize the crystal structures and morphologies of perovskite films, respectively. It was found that the orientation of the crystal changed and the grains became more uniform in Y-MAPbI₃ film, compared with the pure MAPbI₃ perovskite film. The films were used to prepare the resistive switching memory devices with the device structure of Al/Y-MAPbI₃ (MAPbI₃)/ITO-glass. The memory performance of both devices was studied and showed a bipolar resistive switching behavior. The Al/MAPbI₃/ITO device had an endurance of about 328 cycles. In contrast, the Al/Y-MAPbI₃/ITO device exhibited an enhanced performance with a long endurance up to 3000 cycles. Moreover, the Al/Y-MAPbI₃/ITO device also showed a higher ON/OFF ratio of over 10³, long retention time (≥10⁴ s), lower operation voltage (±0.5 V) and outstanding reproducibility. Additionally, the conduction mechanism of the high resistance state transformed from space-charge limited current for a Y free device to the Schottky emission after Y doping. The present results indicate that the Al/Y-MAPbI₃/ITO device has a great potential to be used in high-performance memory devices.

Full-Electrical Writing and Reading of Magnetization States in a Magnetic Junction with Symmetrical Structure and Antiparallel Magnetic Configuration

Full-electrical writing and reading of magnetization states are vital for the development of next-generation spintronic devices with high density and ultralow-power consumption. Here, we proposed a method to realize the full-electrical writing and reading of magnetization states via a structural design, which only requires a symmetrical device structure and an antiparallel magnetic configuration. CrBr₃, h-BN, and 1T-MnSe₂ were selected to construct the device of CrBr₃/h-BN/1T-MnSe₂/h-BN/CrBr₃, where the magnetization of two CrBr₃ layers was fixed to the antiparallel state. By changing the direction and magnitude of the applied electric field, it is proved that the magnetization of 1T-MnSe₂ could be reversed. Moreover, the device energies before and after the magnetization reversal are the same when the applied electric field is removed due to the structural symmetry. Meanwhile, the magnetic anisotropy energy of 1T-MnSe₂ could induce an energy barrier, to guarantee the nonvolatile magnetization reversal in the present device. In addition, the tunnel magnetoresistance ratio was found up to 421%, showing a promising application to full-electrically write and read magnetization in spintronics. The present study likely promotes the development of full-electrical and ultralow-power spintronics devices.

Quercetin inhibited the proliferation and invasion of hepatoblastoma cells through facilitating SIRT6-medicated FZD4 silence

Hepatoblastoma (HB) is a malignant liver tumor that occurs during childhood. The histone deacetylase SIRT6 functions as a tumor suppressor in diverse cancers. Quercetin, as activators and antioxidants of sirtuins, exhibits remarkable anticancer activity in many tumors. However, whether quercetin ameliorates HB is still unclear. In our study, we found that SIRT6 was downregulated in HB tissues and cell lines. Overexpression of SIRT6 observably suppressed cell proliferation and invasion, promoted cell apoptosis. Mechanistically, SIRT6 suppressed frizzled 4 (FZD4) transcription by deacetylating histone H3K9. Upregulation of SIRT6 reduced the protein levels of FZD4 and H3K9ac. Additionally, quercetin treatment could enhance the expression of SIRT6, repress FZD4 level, cell viability and invasion, and promote apoptosis. Overexpression of FZD4 signally reversed quercetin-treated the promotion effect on cell apoptosis, and the inhibition effects on FZD4 expression, cell viability, invasion and Wnt/β-catenin pathway related proteins. In addition, LiCl, an agonist of Wnt/β-catenin pathway, could recover the inhibition effects of quercetin on Wnt/β-catenin pathway related proteins, cell viability and invasion, and promotion effect on cell apoptosis. In vivo mouse xenograft tumor growth assay revealed that quercetin markedly suppressed tumor growth. In conclusion, these results demonstrated that the molecular mechanism of quercetin suppressing HB cell proliferation and invasion, promoting apoptosis was to promote the deacetylation of SIRT6 on FZD4 and inhibit the activation of Wnt/β-catenin pathway.

Expression of miR-207 in renal tissue of renal fibrosis rats and its correlation analysis with protein expression of TGF-β1 and Smad3

OBJECTIVE

This study was designed to analyze the expression of miR-207 in renal tissue of renal fibrosis rats and its correlation with the protein expression of TGF-β1 and Smad3.

MATERIALS AND METHODS

Rat models with renal fibrosis were established via unilateral ureteral obstruction (UUO). Then, the expression levels of miR-207, TGF-β1 and Smad3 in renal tissue of rats were intervened by over-expression vector miR-207 mimic, miR-207 inhibitor and TGF-β/Smad3 signal SIS3 free base, and the effect and mechanism of action of miR-207 on renal fibrosis were analyzed.

RESULTS

In UUO models established in this study, the expression levels of fibrosis related factors TGF-β1, Smad3, Smad2, α-SMA, BMP-7, MMP7 and MMP9 were elevated, and staining results showed that evident fibrosis occurred in renal tissue of rats. Moreover, we also found that the miR-207 expression increased in UUO model rats. After inhibiting miR-207 expression, their degree of renal fibrosis also reduced significantly, and the expression levels of TGF-β1, Smad3, Smad2, α-SMA, BMP-7, MMP7 and MMP9 were inhibited. Besides, miR-207 had a positive correlation with TGF-β1/Smad3 expression. We designed a group of rats, and found that while miR-207 expression was up-regulated, TGF-β1/Smad3 signals were inhibited, and compared with those with up-regulation of miR-207 expression, the severity of renal fibrosis reduced significantly, and the expression of other fibrosis indicators Smad2, α-SMA, BMP-7, MMP7 and MMP9 also reduced dramatically.

CONCLUSIONS

The miR-207 expression in renal tissue of rats with renal fibrosis increased, which was positively correlated with TGF-β1/Smad3, and miR-207 could promote the progression of renal fibrosis through TGF-β1/Smad3 signals.

Efficacy and safety of iguratimod combined with methotrexate vs. methotrexate alone in rheumatoid arthritis : A systematic review and meta-analysis of randomized controlled trials

The current systematic review and meta-analysis aims to evaluate the efficacy and safety of iguratimod (IGU) combined with methotrexate (MTX) versus MTX alone in rheumatoid arthritis (RA). Two independent investigators searched for original randomized controlled trials (RCTs) related to the combination of IGU and MTX in RA published before November 1, 2019, in PubMed, Cochrane Library, Embase, the China National Knowledge Infrastructure (CNKI), the Chinese Biomedical Literature Database (CBM), and WanFang Data. Additionally, we searched clinical trial registry websites. We assessed the methodological quality of the included trials using the Cochrane Collaboration tool and the seven-point Jadad scale. Statistical analyses were performed using Review Manager (RevMan) 5.3 (Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014). Meta-regression and publication bias analyses were performed using Stata version 14 software (StataCorp., College Station, TX, USA). A total of 7 RCTs consisting of 665 participants, with 368 participants in the active arm and 297 in the placebo arm, were included in the meta-analysis. The American College of Rheumatology (ACR) value was better in the IGU + MTX group than in the MTX alone group, with a pooled relative risk (RR) for ACR20 (American College of Rheumatology 20% improvement criteria), ACR50, and ACR70 of 1.40 (95% CI, 1.13-1.74), 2.09 (95% CI, 1.67-2.61), and 2.24 (95% CI, 1.53-3.28), respectively. The results of the meta-analysis demonstrated that there was no statistical significance in adverse events (1.06 (95% CI, 0.92-1.23)). The combined treatment is an effective, safe, and economical treatment option for patients who do not respond well to methotrexate alone or for patients who cannot afford expensive biologics that have no confirmed efficacy.

The complex multi-sectoral impacts of drought: Evidence from a mountainous basin in the Central Spanish Pyrenees

We analyzed the impacts of drought severity on a variety of sectors in a topographically complex basin (the upper Aragón basin 2181 km²) in the Central Spanish Pyrenees. Using diverse data sources including meteorological and hydrological observations, remote sensing and tree rings, we analyze the possible hydrological implications of drought occurrence and severity on water availability in various sectors, including downstream impacts on irrigation water supply for crop production. Results suggest varying responses in forest activity, secondary growth, plant phenology, and crop yield to drought impacts. Specifically, meteorological droughts have distinct impacts downstream, mainly due to water partitioning between streamflow and irrigation channels that transport water to crop producing areas. This implies that drought severity can extend beyond the physical boundaries of the basin, with impacts on crop productivity. This complex response to drought impacts makes it difficult to develop objective basin-scale operational definitions for monitoring drought severity. Moreover, given the high spatial variability in responses to drought across sectors, it is difficult to establish reliable drought thresholds from indices that are relevant across all socio-economic sectors. The anthropogenic impacts (e.g. water regulation projects, ecosystem services, land cover and land use changes) pose further challenges to assessing the response of different systems to drought severity. This study stresses the need to consider the seasonality of drought impacts and appropriate drought time scales to adequately assess and understand their complexity.

[The correlation between polycyclic aromatic hydrocarbons and idiopathic membranous nephropathy]

Objective: To explore the relationship between polycyclic aromatic hydrocarbons (PAHs), the major component of atmospheric pollutant particulate matter 2.5 (PM_2.5) and idiopathic membranous nephropathy (IMN) and its possible mechanisms. Methods: Thirty-five (24 males and 11 females) patients with IMN confirmed by renal biopsy pathology in the First Affiliated Hospital of Zhengzhou University from June to September 2020 were selected as the research group, with an age of (47.3±12.9) years. Meanwhile, patients with secondary membranous nephropathy (SMN, n=10) and minimal-change disease (MCD, n=10) were selected as control group. Blood samples were collected to detect PAHs and heme oxygenase-1 (HO-1), and the relationship of PAHs with clinical indicators and oxidative stress indicator HO-1 was analyzed. Results: Compared with SMN and MCD groups [(2.6±1.7) mg/L and (2.8±1.0) mg/L], the concentration of PAHs in IMN group [(4.1±1.9) mg/L] increased (both P<0.05). The concentration of PAHs was positively correlated with the levels of β2 microglobulin, total cholesterol and 24-hour urine total protein (r=0.509, 0.336, and 0.653, respectively, all P<0.05), but was negatively correlated with the levels of total protein and albumin (r=-0.499,-0.530, respectively, both P<0.05). Additionally, the concentration of PAHs was negatively correlated with the level of HO-1 (r=-0.358, P=0.017). Linear regression analysis showed that the concentration of HO-1 decreased by 1.737 μg/L when the concentration of PAHs increased by 1 mg/L (P=0.035). Conclusion: PAHs have a high level in IMN patients, and may be involved in the occurrence and development of IMN through oxidative stress.

A New Superconducting 3R-WS2 Phase at High Pressure

High-pressure investigation has been shown to be of paramount significance for changing the conventional lattice or bringing fascinating properties, especially inducing superconducting phases. Here we studied the application of pressure to the recently synthesized 2M-WS₂ with the record T_c (8.8 K) among transition metal dichalcogenides (TMDs) at ambient pressure by electrical resistance investigations, synchrotron X-ray studies, and theoretical calculations. T_c in the initial 2M-WS₂ dropped from the maximum to become undetected, accompanied by a phase transition into a semiconductor, 3R-WS₂, at 15 GPa. The successive metallization and superconducting transitions in 3R-WS₂ were observed at 48.8 GPa with T_c ≈ 2.5 K. This is the first experimental case in which superconductivity has been realized in the 3R phase among TMDs. We propose that the degradation of superconductivity in 2M-WS₂ and the reemergence of superconductivity in 3R-WS₂ are mainly attributable to changes in the density of states near the Fermi surface driven by the interlayer coupling.

Dietary Lactobacillus casei can be used to influence intraepithelial lymphocyte migration and modulate mucosal immunity in chicks

1. The role of probiotics in modulating intestinal mucosal immunity in chicks was investigated by measuring migration of intraepithelial lymphocytes (IEL) and cytokine signals in chicks fed on a diet supplemented with the Lactobacillus casei compared with those of chicks fed on an unsupplemented diet.2. Increased numbers of intraepithelial lymphocytes (IEL) were detected in the ileal epithelium at d 3 and d 7 after feeding a diet containing 10⁸ CFU/g L. casei.3. Greater expression of chemokine genes for C-C motif chemokine ligand 3, C-X-C motif chemokine ligand 12, C-C motif chemokine receptor 5, and C-C motif chemokine receptor 9 were detected in the ileum on d 3, suggesting a greater number of IEL was associated with lymphocyte migration through the chemokine signalling pathway.4. After IEL migration, cell proliferation was evident in mucosal epithelial cells on d 14. Evidence of immune responses induced in the ileum from d 3-21 after feeding the diet containing L. casei was shown by the significant (P < 0.05) differences in transforming growth factor-β, secretory immunoglobulin A, interferon-γ, tumour necrosis factor-α, interleukin-4, and interleukin-10.5. These results indicated that feeding L. casei helps guide IEL migration and modulates intestinal mucosal immunity.

[The impact of ambient temperature exposure on emergency calls-a time series analysis based on data of Xuchang and Zhengzhou]

Objective: To investigate the effect of hourly ambient temperature exposure on emergency calls in Xuchang city and Zhengzhou city. Methods: The hourly meteorological data, air pollution data and emergency calls of Xuchang city and Zhengzhou city were collected from January 1, 2017 to October 31, 2019. A distributed lag non-linear model was used to calculate the excess relative risk (ERR). The lag effect and cumulative effect of extreme temperature exposure on emergency calls were evaluated. Results: The relationship between hourly temperature exposure and emergency calls was a U-shaped curve. In Xuchang city and Zhengzhou city, both low and high temperatures would increase the number of hourly emergency calls. The earliest effect of low temperature occurred at a lag of 22 h and 52 h, with ERR values (95%CI) about 0.20% (0.00%, 0.39%) and 0.11% (0.00%, 0.22%), respectively. The earliest effect of high temperature occurred at a lag of 0 h with ERR values about 1.59% (1.09%, 2.09%) and 1.45% (1.22%, 1.69%), respectively. High temperature had the greatest impact on the number of emergency calls of cardiovascular disease at a lag of 4-8 h. The cumulative ERR values (95%CI) of the two cities were 8.70% (4.98%, 12.75%) and 3.89% (2.61%, 5.22%), respectively. Conclusion: High temperature exposure could increase the number of emergency calls within a few hours, while the effect of low temperature would not occur until 22 hours later.

Adrenal metastases: early biphasic contrast-enhanced CT findings with emphasis on differentiation from lipid-poor adrenal adenomas

AIM

To evaluate the accuracy of unenhanced attenuation and early biphasic contrast-enhanced computed tomography (CT) in differentiating adrenal metastases (AMs) from lipid-poor adrenal adenomas (AAs).

MATERIALS AND METHODS

This retrospective study included 37 patients with 50 AMs and 86 patients with 89 lipid-poor AAs. Quantitative data including the longest diameter (LD), the shortest diameter (SD), LD/SD ratio, CT attenuation values (CTu, CTa, CTv), degree of enhancement (DEAP, DEPP, DEpeak, APW, RPW), and peak enhanced/unenhanced (PE/U) CT attenuation ratio were obtained. Qualitative data including enhancement pattern, location, shape, the presence of calcification or haemorrhage, and intra-lesion necrosis were analysed. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were also calculated.

RESULTS

The PE/U ratio (≤1.25), CTu (≥32.2 HU), DEpeak (≤43.15 HU), DEPP (≤37.65 HU), presence of intralesional necrosis, location (bilateral adrenal glands), and irregular shape were significant variables for differentiating AMs from lipid-poor AAs (p<0.05). Among them, PE/U ratio (≤1.25) was of greater value in differentiating the two adrenal diseases, with sensitivity, specificity, area under the receiver operating curve (ROC) curve (AUC) of 92%, 84%, 0.933, respectively. When at least any three of above criteria were combined, the sensitivity, specificity, PPV, and NPV for diagnosing AMs were 88%, 93%, 88%, and 88%, respectively.

CONCLUSIONS

These seven CT criteria are conducive to differentiate AMs from lipid-poor AAs. Early biphasic contrast-enhanced CT is a high-efficient and practical imaging tool in differentiating them.

[Comparison of corneal refractive power and astigmatism measured by the new anterior segment optical coherence tomographic device and Scheimpflug imaging device in age-related cataract patients]

Objective: To compare the difference and agreement of corneal refractive power and astigmatism measured by the new swept-source anterior segment optical coherence tomography (SS-AS-OCT) device (CASIA2) and Scheimpflug imaging device (Pentacam) in age-related cataract patients. Methods: In this cross-sectional study, 112 eyes of 112 patients with age-related cataract were examined before phacoemulsification in the Tianjin Medical University Eye Hospital from April to May 2020. The steep keratometry (Ks), flat keratometry (Kf), mean keratometry (Km), degree and axis of astigmatism of the corneal anterior and posterior surfaces and the total cornea were recorded. The difference in astigmatism was analyzed by the arithmetic method and the vector method. The difference of data was evaluated using Paired t test or Wilcoxon test. The agreement of data was evaluated using Bland-Altman plots. Results: The patients were 44 males and 68 females with an average age of (67±10) years. There were no statistically differences in the Ks and Km values of the corneal anterior surface between the Pentacam and the CASIA2 (both P>0.05). There was significant difference in the Kf values of the corneal anterior surface between the Pentacam and the CASIA2 [(44.24±1.73) D vs. (44.14±1.64) D; t=2.278; P<0.05]. The Ks, Kf, and Km values of the posterior surface of the cornea measured by the Pentacam and the CASIA2 were (-6.60±0.29) D vs. (-6.45±0.28) D, (-6.34±0.27) D vs. (-6.17±0.25) D, and (-6.47±0.26) D vs. (-6.31±0.25) D, respectively. The Ks, Kf, and Km values of the total cornea measured by the two instruments were (45.08±1.84) D vs. (43.94±1.64) D, (44.18±1.85) D vs. (43.02±1.64) D, and (44.63±1.82) D vs. (43.48±1.60) D, respectively. There were significant differences in the Ks, Kf, and Km values of the posterior surface of the cornea and the total cornea (t=-14.440, -13.522, -17.186, 21.016, 21.819, 22.981; all P<0.01). The degree and axis of astigmatism of the corneal anterior and posterior surfaces and the total cornea showed no statistically significant difference (all P>0.05). Vector operation results showed that the astigmatism difference vector (DV) of the Pentacam and the CASIA2 on the anterior surface of the cornea was 0.06 D@57°±0.64 D,>0.50 D in 47 eyes (41.96%). The astigmatism DV on the posterior surface of the cornea was 0.07 D@174°±0.21 D, >0.50 D in 2 eyes (1.79%). The astigmatism DV on the total cornea was 0.13 D@3°±0.69 D,>0.50 D in 59 eyes (52.68%). The results of the two devices were positively correlated (r values of the Ks, Kf, Km, and astigmatism degree on the anterior surface of the cornea were 0.970, 0.968, 0.976, and 0.697, respectively, on the posterior surface of the cornea were 0.918, 0.875, 0.925, and 0.517, respectively, and on the total cornea were 0.951, 0.955, 0.959, and 0.622, respectively; all P<0.01). Bland-Altman analysis showed that the Ks, Kf, Km, and astigmatism degree of the corneal anterior and posterior surfaces measured by the two devices were consistent, with 2.68% to 8.04% of the measured values outside 95% limits of agreement (95%LoA). The 95%LoA of the total corneal Ks, Kf, and Km between the two devices was 0.01 to 2.28 D, 0.06 to 2.27 D, and 0.10 to 2.20 D, respectively, with a wide 95%LoA range and poor consistency. Conclusions: The corneal refractive power and astigmatism measured by the CASIA2 and the Pentacam shows little difference on the anterior surface of the cornea, with good agreement. However, the refractive power results of the posterior surface of the cornea and the total cornea show great difference, suggesting that these two instruments cannot be used interchangeably in clinical practice. (Chin J Ophthalmol, 2021, 57: 48-55).

First principle studies of ammonium chloride under high pressure

Two new phases of NH₄Cl, P2₁/m and Cmma, which are exactly the same as that of NH₄Br, were predicted to be stable within the pressure ranges of 71–107 and 107–300 GPa, respectively.

Effects of botulinum toxin A on endometriosis‑associated pain and its related mechanism

Endometriosis (EMS) is a common disease in women aged 25–45 years, and pain is the main clinical symptom. The primary clinical treatment is surgical excision and drug therapy targeting the ectopic lesions, but these have not been very effective. Botulinum neurotoxin serotype A (BTX-A) has been reported to be useful in the treatment of pain in a variety of diseases. Based on this, the aim of the present study was to explore the therapeutic effect and mechanism of BTX-A on EMS. A model of nerve injury induced by oxygen glucose deprivation (OGD) was constructed in PC12 cells and EMS mice. Model cells and mice were treated with different concentrations of BTX-A to observe the changes in pain behavior, to detect cell viability and the secretion of norepinephrine (NE) and methionine enkephalin (M-EK) in cells and the spinal cord, and to evaluate the expression of apoptosis-related molecules in spinal cord nerves. The results revealed that BTX-A significantly reduced the amount of writhing in model mice, enhanced the activity of PC12 OGD cells, increased the secretion of NE and M-EK in model cells and the spinal cord of mice, and decreased the apoptosis of neural cells in the spinal cord of the model mice. Therefore, it was hypothesized that BTX-A may alleviate the pain induced by EMS by increasing the secretion of analgesic substances and promoting the repair of nerve injury. The present study provided a theoretical basis for the treatment of pain induced by EMS.

The expression and significance of lncRNA HOST2 and microRNA let-7b in HPV-positive cervical cancer tissues and cell lines

OBJECTIVE

This study attempted to investigate the expression and significance of lncRNA HOST2 (human ovarian cancer-specific transcript 2) and microRNA let-7b in human papillomavirus (HPV)-positive cervical cancer (CC) tissues and cell lines.

PATIENTS AND METHODS

The expression of levels of HOST2 and let-7b were detected by qRT-PCR in HPV-positive CC tissues and cell lines. The HPV-positive CaSki and HeLa cells were divided into the Blank, NC, pcDNA3.0-HOST2, siHOST2, let-7b mimic, and pcDNA3.0-HOST2+let-7b mimic groups. Dual-luciferase reporter gene assay was employed to verify the targeting relationship between HOST2 and let-7b, MTT and flow cytometry to determinate cell proliferation and apoptosis, and wound-healing and transwell assays to evaluate cell migration and invasion capabilities.

RESULTS

HOST2 was up-regulated but let-7b was down-regulated in HPV-positive CC tissues and cells. Dual-luciferase reporter gene assay confirmed the targeting relationship between HOST2 and let-7b. Over-expressed HOST2 reduced let-7b expression, promoted proliferation migration and invasion and inhibited the apoptosis of CaSki and HeLa cells; however, silencing HOST2 or overexpressing let-7b enhanced the expression of let-7b, inhibited proliferation migration and invasion, and promoted the apoptosis of CaSki and HeLa cells, and let-7b mimic could reverse the promoting effect of HOST2 on the growth of CC cells.

CONCLUSIONS

HOST2 was upregulated in HPV-positive CC tissues and cells, which could promote the proliferation, migration and invasion, but inhibit the apoptosis of HPV-positive CC cells via inhibition of let-7b.

Strain-engineering enables reversible semiconductor–metal transition of skutterudite IrAs3

Green strain engineering makes the semiconductor-to-metal transition of skutterudite IrAs₃ possible.

Interface hybridization and spin filter effect in metal-free phthalocyanine spin valves

Spin–orbit coupling has been regarded as the core interaction to determine the efficiency of spin conserved transport in semiconductor spintronics. Here, we show the spin filter effect should be responsible for the magnetoresistance of H₂Pc device.

Hydrogen-bond enhancement triggered structural evolution and band gap engineering of hybrid perovskite (C6H5CH2NH3)2PbI4 under high pressure

Hybrid organic–inorganic perovskites (HOIPs) have gained substantial attention due to their excellent photovoltaic and optoelectronic properties.

Impact of knee varus and valgus deformity on alignment in lower extremities after total knee arthroplasty (TKA)

OBJECTIVE

To investigate the impact of knee varus and valgus in varying degrees on the alignment in lower extremities of patients who received the total knee arthroplasty (TKA).

PATIENTS AND METHODS

We retrospectively analyzed the condition of varus and valgus deformity in full-length X-ray films of double lower extremities in weight-bearing position of 120 patients before and after they firstly received the TKA between March 2012 and May 2014 to discover the impact of knee varus and valgus in varying degrees on the alignment in lower extremities of patients who received the total knee arthroplasty (TKA). 120 patients were divided into three groups by the pre-operative hip-knee-ankle angle (HKA), the HKAs of three groups were compared after operation, and linear regression analysis was conducted to identify the correlation between pre- and post-operative HKAs. In addition, comparison between the pre- and post-operative lean of arms and legs (LMAL) was carried out to explore the variations before and after operation as well as the differences in the average variations among three groups.

RESULTS

The differences were statistically significant in comparison of the pre- and post-operative HKAs and medial proximal tibia angles (MPTA) of all affected extremities (p<0.05), but no statistically significant difference was shown in comparison between the pre- and post-operative knee physical valgus angles (KPVA) (p>0.05). The post-operative lengths of 86.57% of affected extremities (116/134) were longer than those before operation with statistically significant differences (p<0.05). However, no statistically significant difference was identified in comparison between the pre- and post-operative lengths of extremities that did not receive any operation (p>0.05). The ratios of HKAs between -3° and 3° in normal group, mild-deformity group and severe-deformity group were respectively 90.48%, 81.25%, and 34.69% with a statistically significant difference (p<0.05). Besides, the scatter plot revealed that there was a linear regression relation between pre- and post-operative HKAs (F=51.197, p<0.05). There were statistically significant differences in comparisons of the pre-operative KPVA and MPTAs among three groups (p<0.05).

CONCLUSIONS

Severe knee varus and valgus deformity can increase the deviation of alignment in lower extremities after TKA, and most of LMALs after TKA are longer than those before TKA, and the most significant extension is identified in severe varus and valgus deformity.

Efficacy and immunogenicity of a live L. acidophilus expressing SAD epitope of transmissible gastroenteritis virus as an oral vaccine

Transmissible gastroenteritis virus (TGEV) causes great economic loss to swine industry worldwide. Vaccination is an important method to control the TGEV infection. In this study, a TGEV oral vaccine was generated by transferring a eukaryotic expression recombinant plasmid carrying the SAD (A and D antigenic sites of the S protein) epitope of TGEV into a swine-origin Lactobacillus acidophilus (L. acidophilus). In orally immunized BALB/c mice, the TGEV L. acidophilus oral vaccine induced significantly higher level of SIgA antibodies specific to TGEV compared with the mice immunized with a commercial inactivated TGEV vaccine and similar levels of IgG specific to TGEV as the inactivated vaccine. Furthermore, the TGEV L. acidophilus oral vaccine induced higher levels of IFN-γ, which suggested that the vaccine was able to induce immune response. In brief, this novel TGEV L. acidophilus oral vaccine could induce high levels of both mucosal and humoral immune responses, which has a potential to be used in the pig industries in the future. Keywords: transmissible gastroenteritis virus (TGEV); live L. acidophilus oral vaccine; SIgA antibody; IgG antibody; IFN-γ; IL-4.

Structure and superconductivity of protactinium hydrides under high pressure

We systematically study the stability, crystal structure, electronic property, and superconductivity of protactinium hydride (PaH _n ) (n  =  1-9) at a pressure range of 1 atm to 300 GPa by using the first principle of density functional theory. PaH _n compounds are very rich, featuring six stoichiometries, such as PaH, PaH₃, PaH₄, PaH₅, PaH₈ and PaH₉. PaH₈ possesses the highly symmetrical crystal structure Fm-3m with cubic H8 units, which is predicted to be thermodynamically stable above 32 GPa. This phase maintains a dynamically stable decompression at 10 GPa. Electron-phonon coupling (EPC) calculations show that Fm-3m-PaH₈ exhibits high superconducting critical transition temperature (T _c) value of 79 K at 10 GPa due to a strong EPC and large logarithmic average frequency. The T _c values of Fm-3m-PaH₈ decrease with increasing pressure. Interestingly, superconducting PaH₈ appears at low pressure, prompting experimental research.

New Metallic Ordered Phase of Perovskite CsPbI3 under Pressure

Pressure-induced electronic structure transition from insulating phase to metal state is a potential new paradigm for halide perovskites. The metallization based on these materials may afford a novel motif toward realizing new electronic properties even superconductivity phenomenon. Herein, how static compression modulates the crystal and electronic structure of typical perovskite semiconductors cesium lead iodine (CsPbI3) by both experimental and theoretical studies is reported. The comprehensive studies discover the insulator-metal transition of CsPbI3 at 39.3 GPa, and reveal the key information behind the electronic transition. The perovskite's precise structural evolution is tracked upon compression, from orthorhombic Pnma phase to monoclinic C2/m structure before the metallic transition. More interestingly, the C2/m phase has the most distorted octahedra and the shortest Pb-I bond length relative to the average bond length that is ever reported in a halide perovskite structure. The electronic transition stems from the structural changes accompanied by the anomalously self-distorted octahedra. These studies show that pressure can significantly alter the structural and electronic properties of these technologically important perovskites.

High-temperature superconductivity in ternary clathrate YCaH12 under high pressures

Binary hydrogen-rich compounds with H clathrate structures can serve as high-temperature superconductors under high pressures. Here, a novel ternary clathrate structure YCaH₁₂ with space group Pm-3m is uncovered at high pressure using ab initio methods. It is predicted that YCaH₁₂ can be stable above 180 GPa and decomposes into YH₆ and CaH₆ above 257 GPa. Our calculations show that YCaH₁₂ is a potential high-temperature superconductor with T _c of 230 K at 180 GPa owing to the strong electron-phonon coupling related to the optical phonon softening of H-cages. The pre-eminent pressure-induced superconductive behavior under attainable pressure is encouraging in the ternary hydrides.