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.