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The structure of niobium-doped SrBiTiO was calculated by using density function and discrete variation method (DFT-DVM). By comparing the total energy of different doping sites, the total energy is found to be lower when Nb ion was substituted into the Ti site in the upper perovskite layer, which is far from the two bismuth (Bi) ions in the perovskite layer. The bonding strength of Nb (3)-O increases and the electronic conductivity of the SBT decreases after Nb doping. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 [ABSTRACT FROM AUTHOR]

In this paper, the microwave-assisted molten salt method (MAMSS) and molten salt method (MSS) were used to synthesize SrBi4Ti4O15 (SBT). The phase constitution was determined by powder X-ray diffraction and the microstructure of powder was examined by scanning electron microscopy. In contrast to the conventional MSS method, MAMSS produces more distinct plate-like grains and synthesizes both SBT and Bi4Ti3O12 (BTO) at 600°C with a 30-min soaking time. The increase of temperature and soaking time can make the plate-like grains of BTO more distinct. [ABSTRACT FROM AUTHOR]

The single-phase Ba(Mg1/3 Nb2/3)O3 (BMN) powder was successfully prepared by the KCl molten salt synthesis (MSS) method. The temperature for single-phase BMN powders by MSS was about 400°C lower than that by the solid-phase method. The average particle size (APS) was about 0.91 μm at 900°C and increased with increasing synthesis temperature. Based on the APS, the activation energy for particle growth in the MSS, whose value was 64.1 kJmol-1, was attained. The sinterability of the powder prepared by MSS method was better than that prepared by solid-phase method. [ABSTRACT FROM AUTHOR]

Abstract: The Aurivillius-type Bi2VO5.5-δ series doped by magnetic cations may have a significant electronic contribution to their total conductivity and special magnetoelectric properties which extend potential applications to magnetoelectronic and spintronic fields. Bi2(V1-xMnx)O5.5-δ and (Bi2-xMnx)VO5.5-δ (x=0.10–0.30) compounds with nominal composition doped by manganese cation on the Bi- or V-site were prepared via a solid-state reaction. Results show that partial substitution of Mn on the V-site stabilizes Bi2(V1-xMnx)O5.5-δ in the high-temperature tetragonal structure of Bi2VO5.5-δ for compositions in the range 0.10≤x<0.25. The geometric magnetic frustration was observed through magnetic susceptibility analysis. The crystal structure was refined by the Rietveld method based on a four-oxygen-site model. The resulting solid-solution limit confirms the equatorial vacancy model which assumes that all vacancies are located on the equatorial oxygen sites. The possible substitution mechanism is determined which supports V↔Mn, rather than Bi↔Mn in the MnO-doped Bi2VO5.5-δ series. [Copyright &y& Elsevier]

The effect of BaWO4 addition on the microstructures, the phase formation, 1:2 ordering and microwave dielectric properties of Ba(Mg1/3Nb2/3)O3 was investigated. Ba5Nb4O15 and BaWO4 secondary phases were found in all specimens containing BaWO4. The B-site ordering parameter (S) and the lattice constant (c/a) values increased with BaWO4 increased. Ba(Mg1/3Nb2/3)O3 ceramics with BaWO4 addition can be sintered to 95% theoretical density at 1500 °C due to the liquid phase effect of BaWO4. At 0.03 mol BaWO4, the specimen shows the maximum Qf value of 82 300 GHz attributed to high density and ordering degree. The decrease of Qf value with further addition of BaWO4 is due to the increase of secondary phases BaWO4 and Ba5Nb4O15, which have lower Qf values than Ba(Mg1/3Nb2/3)O3 phase. The variation of #x03B5;r and τf was also explained based on the logarithmic mixture rule and the volume mixture ruler, respectively. [Copyright &y& Elsevier]

Postpartum elevation of alanine aminotransferase (ALT) in mothers with chronic hepatitis B (CHB) presents a significant clinical challenge. However, the existing literature demonstrates inconsistencies regarding its incidence and predictors in mothers infected with the hepatitis B virus (HBV). Recent advancements in antiviral prophylaxis against mother-to-child transmission of HBV and postpartum cessation of antiviral therapy further complicate this issue. Our literature review, spanning PubMed, and two Chinese-language databases (CNKI and Wanfang) from 1 January 2000 to 31 December 2023 aimed to consolidate and analyse available data on the frequency and severity of postpartum ALT flares, identify risk factors, and propose a management algorithm. Data from 23 eligible studies involving 8,077 pregnant women revealed an overall incidence of postpartum ALT elevation: 25.7% for mild cases, 4.4% for moderate cases, and 1.7% for severe cases. In the subgroup of mothers who were HBeAg-positive and on antiviral prophylaxis for preventing mother-to-child transmission, postpartum intermediate and severe ALT elevations were reported with pooled rates of 5.9% and 0.8%, respectively. Importantly, none resulted in mortality or necessitated liver transplantation. Identified risk factors for postpartum ALT flares in mothers with CHB included HBV DNA levels, ALT levels during pregnancy, postpartum cessation of antiviral treatment, and HBeAg status. By leveraging this evidence and recent data on predictors of intermediate or severe postpartum ALT flares, we propose a risk-stratified algorithm for managing postpartum ALT elevation and selecting therapy in mothers with CHB, tailoring different approaches for treatment-naive vs treatment-experienced populations. These recommendations aim to provide guidance for clinical decision-making and enhance patient outcomes., Competing Interests: C.Q.P. received institutional research grants from Gilead Sciences and Wuxi Hisky Medical Technologies Co., Ltd. Other authors have no financial interests to be disclosed., (© The Author(s) 2024. Published by Oxford University Press and Sixth Affiliated Hospital of Sun Yat-sen University.)

Background: Radiofrequency ablation (RFA) is an effective therapy for hepatocellular carcinoma (HCC). However, incomplete radiofrequency ablation (IRFA) can promote the progression of residual cancer cells, which is a serious problem in the clinical application of RFA. Therefore, it is of great significance to explore the mechanism and countermeasures of the progression of residual tumors after IRFA. Our previous study confirmed that IRFA can activate the hypoxia/ autophagy pathway of residual tumors in mice and then induce the proliferation of residual tumor cells. Additionally, we found a metal ruthenium complex [Ru(bpy)2(ipad)](ClO4)2 (Ru, where bpy = 2,2'-bipyridine and ipad = 2-(anthracene-9,10-dione-2-yl)imidazo[4,5-f][1,10]phenanthroline) can effectively inhibit hypoxia-inducible factor (HIF-1α) and has good anti-tumor effect in a hypoxic environment; however, whether Ru could suppress the proliferation of residual tumor cells after IRFA is unknown., Objective: This study intends to evaluate the effect of Ru in suppressing the proliferation of residual hepatocellular carcinoma after IRFA in a mice model., Methods: The Hepa1-6 xenograft mouse model was established in C57BL/6 mice to simulate clinical IRFA. H&E staining was used to evaluate the biosafety of major organs in the treated mice. TUNEL assay was employed to assess the antitumor effect. Immunohistochemically and immunofluorescence staining was performed to detect the expression of HIF-1α and autophagy-related proteins. The ELISA assay was used to examine the cytokines of interferon-gamma (IFN-γ) and interleukin 10 (IL-10)., Results: Our findings revealed that the residual tumor relapsed via the HIF-1α/LC3B/P62 autophagy- related pathway after IRFA, while Ru could suppress this process. In addition, it was demonstrated that Ru could effectively activate the immune system of the mice and reverse the tumor immune suppression microenvironment after IRFA., Conclusion: The ruthenium complex Ru could suppress the proliferation of residual hepatocellular carcinoma cells after IRFA in the mice model. This study introduces a novel approach that combines the use of ruthenium complexes with IRFA, offering a potential solution to address the reoccurrence of residual liver cancer following IRFA in clinical settings., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Acute liver failure (ALF) is a severe liver disease caused by disruptions in the body's immune microenvironment. In the early stages of ALF, Kupffer cells (KCs) become depleted and recruit monocytes derived from the bone marrow or abdomen to replace the depleted macrophages entering the liver. These monocytes differentiate into mature macrophages, which are activated in the immune microenvironment of the liver and polarized to perform various functions. Macrophage polarization can occur in two directions: pro-inflammatory M1 macrophages and anti-inflammatory M2 macrophages. Controlling the ratio and direction of M1 and M2 in ALF can help reduce liver injury. However, the liver damage caused by pyroptosis should not be underestimated, as it is a caspase-dependent form of cell death. Inhibiting pyroptosis has been shown to effectively reduce liver damage induced by ALF. Furthermore, macrophage polarization and pyroptosis share common binding sites, signaling pathways, and outcomes. In the review, we describe the role of macrophage polarization and pyroptosis in the pathogenesis of ALF. Additionally, we preliminarily explore the relationship between macrophage polarization and pyroptosis, as well as their effects on ALF., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Xie and Ouyang.)

Xpert Xpress Flu/RSV is a fast and automated real-time nucleic acid amplification tool for detecting influenza virus and respiratory syncytial virus (RSV). The aim of this study was to verify the accuracy of Xpert Xpress Flu/RSV for detecting influenza virus and RSV. PubMed, EMBASE, Cochrane Library, and Web of Science databases were searched up to October 2020. The quality of the original research was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 guidelines. Meta-DiSc 1.4 software was used to analyze the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and summary receiver operating characteristic curve. Deek's funnel plot asymmetry test was used to evaluate the publication bias using the Stata 12.0 software. Ten studies with 25 fourfold tables were included in the analysis. The sensitivity of Xpert Xpress Flu/RSV for detecting influenza A, influenza B, and RSV were 0.97, 0.98, and 0.96, respectively, and the specificities were 0.97, 1.00, and 1.00, respectively. Compared with other common clinical real-time reverse transcription-polymerase chain reaction (RT-PCR), Xpert Xpress Flu/RSV is a valuable tool for diagnosing influenza virus and RSV with high sensitivity and specificity.

Background: To date, studies have shown inconsistent results of treatment with bone marrow-derived stem cells (BMDSC) for patients with liver cirrhosis. This study aims to compare the efficacy and safety of BMDSC and standard therapy for liver cirrhosis., Methods: Articles from PubMed, Embase, and the Cochrane library were searched from inception to April 2018. The index included Model for End-stage Liver Disease (MELD), alanine aminotransferase (ALT), albumin, total bilirubin (TBIL), prothrombin time (PT), Child-Pugh score, and all-cause mortality., Results: A total of 9 studies with a total of 424 patients with liver cirrhosis were included in final meta-analysis. BMDSC therapy was associated with lower MELD within 3 months (P = .010), while it had no significant impact on MELD after 6 months (P = .074). There were no differences between BMDSC and standard therapy for ALT within 3 months (P = .336) and after 6 months (P = .379). BMDSC did not affect albumin level within 3 months (P = .196) and after 6 months (P = .840). BMDSC reduced the TBIL level within 3 months (P = .037) and was not associated with the TBIL level after 6 months (P = .914). There were no differences between BMDSC and standard therapy for PT within 3 months (P = .167) and after 6 months (P = .484). The Child-Pugh scores within 3 months (P = .342) and after 6 months (P = .133) were not associated with BMDSC treatment for liver cirrhosis patients. Finally, the BMDSC was not associated with the risk of all-cause mortality, as compared with standard therapy (P = .622)., Conclusions: BMDSC treatment for patients with liver cirrhosis could improve short-term MELD and TBIL, but not the risk of mortality, as compared with standard therapy.

Objective: To investigate the changes in the expressions of p53, DKK (the inhibitor of Wnt pathway) and phosphorylated tau in rat bilateral hippocampus after beta-amyloid peptide (beta-AP) (25-35) injection, and observe the effect of saponin B from Anemarrhena asphodeloides Bunge (SAaB) in this model., Methods: After bilateral injection of beta-AP (25-35) into the hippocampus of rats, RT-PCR was performed for observing the changes in p53 and DKK mRNA expressions and immunochemistry carried out to detect the changes in phosphorylated tau protein., Results: RT-PCR showed increased p53 and DKK mRNA expression and immunochemistry revealed increased phosphorylated tau-positive cells in rat hippocampus after beta-AP (25-35) injection, and administration of SAaB significantly ameliorated these changes., Conclusion: SAaB can significantly ameliorate beta-AP-induced tau hyperphosphorylation by inhibiting increased p53 and DKK mRNA expressions in response to beta-AP injection.

Objective: To investigate the effects of timosaponins, one group of the two major components of Anemarrhean asphodeloides Bge, on the learning and memory capacities of rats with dementia induced by amyloid beta-peptide (25-35) [Abeta (25-35)]., Methods: Sixty SD rats were randomized into 6 groups (n=10) and except for those in the control group, all other rats were subjected to lateral cerebral ventriclar injection of aggregated Abeta (25-35) to prepare rat models of dementia. Twenty- four hours after the injection, the rats received intragastric administration of timosaponins at 3 different doses (treatment group) or Ginkgo biloba extract EGB761 on a daily basis for 14 consecutive days. From postoperative days 8 to 14 after Abeta (25-35) injection, Morris water maze test was performed to evaluate the effects of Abeta (25-35) and the therapeutic agents timosaponins on the learning and memory capacity of the rats. On day 14, the level of malonaldehyde (MDA), superoxide dismutase (SOD) activity and total antioxidation capacity in the brain tissue of the rats were measured., Results: Abeta (25-35) induced significant learning and memory impairment in the rats, which had lowered SOD activity and total antioxidation capacity (P<0.01) with elevated MDA level (P<0.05). Compared with the rats in dementia model group, those receiving timosaponin treatment at different doses all manifested alleviation of learning and memory impairment (P<0.05), with enhanced SOD activity (P<0.05) and total antioxidation capacity (P<0.01) and reduced MDA level (P<0.05) in the brain tissue., Conclusion: Timosaponins can remarkably enhance the learning and memory capacities in rats with Abeta (25-35)-induced dementia, presumably in relation to their actions to promote the scavenging of the free radicals.

Objective: To observe the effects of Yizhi capsule, a preparation of traditional Chinese drugs on delayed neuronal death in the hippocampal CA1 region and memory function of rats after ischemia-reperfusion injury., Methods: Rat models of acute reperfusion injury after global cerebral ischemia were induced by vertebral and carotid arteries occlusion, and 1, 2, 4, 8 and 40 d after model establishment, the neurons in the rat hippocampal CA1 region were obtained and immunohistochemically stained for counting. Morris water maze test was performed to observe the learning and memory capacities of the rats 40 d after the injury., Results: The number of normal neurons was significantly higher in the rats treated with Yizhi capsule (100 mg/kg.b.w.) than in those without the treatment, and the former group of rats used significantly shorter time in finding the platform under the water surface in Morris water maze test., Conclusion: Yizhi capsule may protect the neurons in the hippocampal CA1 region and improve on the learning and memory dysfunction after global ischemia/reperfusion injury in rats.

The proteins encoded by the Brassica juncea chitinase gene BjCHI1 and its derived genes BjCHI2 and BjCHI3 were expressed by Multi-copy Pichia expression system. The chitinase activity of FPLC purified BjCHI1, BjCHI2 and BjCHI3 were tested and the results showed that all the three proteins degraded both CM-chitin-RBV and colloidal chitin. The Km values of BjCHI1, BjCHI2 and BjCHI3 for CM-chitin-RBV were estimated as 0.799 mg/mL, 0.544 mg/mL and 0.793 mg/mL, respectively. When the colloidal chitin was used as substrate, the Km values were 0.281 mg/mL, 0.388 mg/mL and 1.643 mg/mL, respectively, indicating chitin-binding domain can increase affinity of chitinase to insoluble substrate. In the agglutination activity assay, only BjCHI1 shows activity when the protein concentration was more than 33 micrograms/mL, while BjCHI2 and BjCHI3 without agglutination activity even when the concentration was increased as high as 800 micrograms/mL. This means that the two chitin-binding domains in BjCHI1 are essential for agglutination and BjCHI1 is the first protein which shows both chitinase and agglutination activity identified so far in plants.