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The thrust bearing, as the only part bearing the axial load, is extremely important in vertical hydroelectric generating units. Its working condition directly affects the safe and reliable operation of the hydroelectric generating unit. However, during operation, the oil film is easily damaged under the influence of complex factors. Installation deviation is a key point that can cause temperature and pressure changes in the oil film, affecting the force on the bearing. This article takes the thrust bearing model of the 1000 MW Francis turbine unit of the Baihetan Power Station as the research object. Based on the fluid–solid coupling theory and CFD technology, the oil film characteristics of thrust bearings are analyzed, and the influence of inclination angles and installation deviation on the oil film flow performance of thrust bearings is discussed. The results show that as the inclination angle changes from 0.0030° to 0.0048°, the axial force changes from 856 t to 368 t, and there is an approximate linear correlation between them. The radial installation deviation has an effect on the axial force. Under the optimal working condition of an inclination angle of 0.0039°, when the radial deviation of the pad changes from 0 mm to 1 mm, the axial force changes from 1573 t to 1275 t. In the process of unit installation, it is necessary to pay attention to the installation deviation of the pad. The results provide guidance for the installation of the bearing, which helps to ensure the safe and stable operation of the station.

MicroRNAs are short regulatory RNAs that negatively modulate protein expression at a post-transcriptional and/or translational level and are deeply involved in the pathogenesis of several types of cancers. Specifically, microRNA-221 (miR-221) is overexpressed in many human cancers, wherein accumulating evidence indicates that it functions as an oncogene. However, the function of miR-221 in human osteosarcoma has not been totally elucidated. In the present study, the effects of miR-221 on osteosarcoma and the possible mechanism by which miR-221 affected the survival, apoptosis, and cisplatin resistance of osteosarcoma were investigated.Real-time quantitative PCR analysis revealed miR-221 was significantly upregulated in osteosarcoma cell lines than in osteoblasts. Both human osteosarcoma cell lines SOSP-9607 and MG63 were transfected with miR-221 mimic or inhibitor to regulate miR-221 expression. The effects of miR-221 were then assessed by cell viability, cell cycle analysis, apoptosis assay, and cisplatin resistance assay. In both cells, upregulation of miR-221 induced cell survival and cisplatin resistance and reduced cell apoptosis. In addition, knockdown of miR-221 inhibited cell growth and cisplatin resistance and induced cell apoptosis. Potential target genes of miR-221 were predicted using bioinformatics. Moreover, luciferase reporter assay and western blot confirmed that PTEN was a direct target of miR-221. Furthermore, introduction of PTEN cDNA lacking 3'-UTR or PI3K inhibitor LY294002 abrogated miR-221-induced cisplatin resistance. Finally, both miR-221 and PTEN expression levels in osteosarcoma samples were examined by using real-time quantitative PCR and immunohistochemistry. High miR-221 expression level and inverse correlation between miR-221 and PTEN levels were revealed in osteosarcoma tissues.These results for the first time demonstrate that upregulation of miR-221 induces the malignant phenotype of human osteosarcoma whereas knockdown of miR-221 reverses this phenotype, suggesting that miR-221 could be a potential target for osteosarcoma treatment.

BACKGROUND: Limb-salvage surgery has been well recognized as a standard treatment and alternative to amputation for patients with malignant bone tumors. Various limb-sparing techniques have been developed including tumor prosthesis, allograft, autograft and graft-prosthesis composite. However, each of these methods has short- and long-term disadvantages such as nonunion, mechanical failures and poor limb function. The technique of intracorporeal devitalization of tumor-bearing bone segment in situ by microwave-induced hyperthermia after separating it from surrounding normal tissues with a safe margin is a promising limb-salvage method, which may avoid some shortcomings encountered by the above-mentioned conventional techniques. The purpose of this study is to assess the healing process and revitalization potential of the devitalized bone segment by this method in a dog model. In addition, the immediate effect of microwave on the biomechanical properties of bone tissue was also explored in an in vitro experiment. METHODS: We applied the microwave-induced hyperthermia to devitalize the distal femurs of dogs in situ. Using a monopole microwave antenna, we could produce a necrotic bone of nearly 20 mm in length in distal femur. Radiography, bone scintigraphy, microangiography, histology and functional evaluation were performed at 2 weeks and 1, 2, 3, 6, 9 and 12 months postoperatively to assess the healing process. In a biomechanical study, two kinds of bone specimens, 3 and 6 cm in length, were used for compression and three-point bending test respectively immediately after extracorporeally devitalized by microwave. FINDINGS: An in vivo study showed that intracorporeally and in situ devitalized bone segment by microwave had great revitalization potential. An in vitro study revealed that the initial mechanical strength of the extracorporeally devitalized bone specimen may not be affected by microwave. CONCLUSION: Our results suggest that the intracorporeal microwave devitalization of tumor-bearing bone segment in situ may be a promising limb-salvage method.

BACKGROUND: If a critical nerve is circumferentially involved with tumor, radical surgery intended to cure the cancer must sacrifice the nerve. Loss of critical nerves may lead to serious consequences. In spite of the impressive technical advancements in nerve reconstruction, complete recovery and normalization of nerve function is difficult to achieve. Though irreversible electroporation (IRE) might be a promising choice to treat tumors near or involved critical nerve, the pathophysiology of the nerve after IRE treatment has not be clearly defined. METHODS: We applied IRE directly to a rat sciatic nerve to study the long term effects of IRE on the nerve. A sequence of 10 square pulses of 3800 V/cm, each 100 µs long was applied directly to rat sciatic nerves. In each animal of group I (IRE) the procedure was applied to produce a treated length of about 10 mm. In each animal of group II (Control) the electrodes were only applied directly on the sciatic nerve for the same time. Electrophysiological, histological, and functional studies were performed on immediately after and 3 days, 1 week, 3, 5, 7 and 10 weeks following surgery. FINDINGS: Electrophysiological, histological, and functional results show the nerve treated with IRE can attain full recovery after 7 weeks. CONCLUSION: This finding is indicative of the preservation of nerve involving malignant tumors with respect to the application of IRE pulses to ablate tumors completely. In summary, IRE may be a promising treatment tool for any tumor involving nerves.

Abstract The aim of this study was to evaluate the effects of C-type natriuretic peptide (CNP) treatment prior to in vitro maturation (IVM) on mitochondria biogenesis in bovine oocyte matured in vitro and explore the related causes. The results showed that treatment with CNP before IVM significantly improved mitochondrial content, elevated the expression of genes related to mitochondria biogenesis, and increased the protein levels of phosphorylation of cAMP-response element binding protein (p-CREB) in bovine oocytes following IVM. However, further studies revealed that treatment with CNP before IVM could not increased the protein levels of p-CREB in bovine oocytes when natriuretic peptide receptor 2 activities was inhibited using the relative specific inhibitor Gö6976. In addition, treatment with CNP before IVM could not improved mitochondrial content or elevated the expression of genes related to mitochondria biogenesis in bovine oocytes when CREB activities was abolished using the specific inhibitor 666–15. In summary, these results provide evidence that treatment of bovine oocytes with CNP before IVM promotes mitochondrial biogenesis in vitro, possibly by activating CREB.

AimsHyperglycemia is one of the adverse effects of tacrolimus (TAC), but the underlying mechanism is not fully identified. We used multi-omics analysis to evaluate the changes in the gut microbiota and metabolic profile of rats with TAC-induced diabetes.MethodsTo establish a diabetic animal model, Sprague Dawley rats were divided randomly into two groups. Those in the TAC group received intraperitoneal injections of TAC (3 mg/kg) for 8 weeks, and those in the CON group served as the control. 16S rRNA sequencing was used to analyze fecal microbiota. The metabolites of the two groups were detected and analyzed by nontargeted and targeted metabolomics, including amino acids (AAs), bile acids (BAs), and short-chain fatty acids (SCFAs).ResultsThe rats treated with TAC exhibited hyperglycemia as well as changes in the gut microbiota and metabolites. Specifically, their gut microbiota had significantly higher abundances of Escherichia-Shigella, Enterococcus, and Allobaculum, and significantly lower abundances of Ruminococcus, Akkermansia, and Roseburia. In addition, they had significantly reduced serum levels of AAs including asparagine, aspartic acid, glutamic acid, and methionine. With respect to BAs, they had significantly higher serum levels of taurocholic acid (TCA), and glycochenodeoxycholic acid (GCDCA), but significantly lower levels of taurodeoxycholic acid (TDCA) and tauroursodeoxycholic acid (TUDCA). There were no differences in the levels of SCFAs between the two groups. Correlations existed among glucose metabolism indexes (fasting blood glucose and fasting insulin), gut microbiota (Ruminococcus and Akkermansia), and metabolites (glutamic acid, hydroxyproline, GCDCA, TDCA, and TUDCA).ConclusionsBoth AAs and BAs may play crucial roles as signaling molecules in the regulation of TAC-induced diabetes.

ABSTRACT Lipid droplets (LDs) are dynamic organelles that participate in the regulation of lipid metabolism and cellular homeostasis inside of cells. LD-associated proteins, also known as perilipins (PLINs), are a family of proteins found on the surface of LDs that regulate lipid metabolism, immunity, and other functions. In silkworms, pébrine disease caused by infection by the microsporidian Nosema bombycis (Nb) is a severe threat to the sericultural industry. Although we found that Nb relies on lipids from silkworms to facilitate its proliferation, the relationship between PLINs and Nb proliferation remains unknown. Here, we found Nb infection caused the accumulation of LDs in the fat bodies of silkworm larvae. The characterized perilipin1 gene (plin1) promotes the accumulation of intracellular LDs and is involved in Nb proliferation. plin1 is similar to perilipin1 in humans and is conserved in all insects. The expression of plin1 was mostly enriched in the fat body rather than in other tissues. Knockdown of plin1 enhanced Nb proliferation, whereas overexpression of plin1 inhibited its proliferation. Furthermore, we confirmed that plin1 increased the expression of the Domeless and Hop in the JAK-STAT immune pathway and inhibited Nb proliferation. Taken together, our current findings demonstrate that plin1 inhibits Nb proliferation by promoting the JAK-STAT pathway through increased expression of Domeless and Hop. This study provides new insights into the complicated connections among microsporidia pathogens, LD surface proteins, and insect immunity.IMPORTANCELipid droplets (LDs) are lipid storage sites in cells and are present in almost all animals. Many studies have found that LDs may play a role in host resistance to pathogens and are closely related to innate immunity. The present study found that a surface protein of insect lipid droplets could not only regulate the morphological changes of lipid droplets but also inhibit the proliferation of a microsporidian pathogen Nosema bombycis (Nb) by activating the JAK-STAT signaling pathway. This is the first discovery of the relationship between microsporidian pathogen and insect lipid surface protein perilipin and insect immunity.

Abstract Background Vaccination has been proven to be an effective approach against the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to determine the acceptance rate and factors influencing acceptance of COVID-19 vaccination among people living with HIV (PLWH) in Guangxi, China. Methods A cross-sectional survey was carried out in five cities in Guangxi, China from May 7 to June 1, 2021. Questionnaires on the acceptance of COVID-19 vaccination and the related factors were conducted among PLWH recruited by simple random sampling. Univariate and multivariate logistic regression analyses were performed to identify factors associated with acceptance of COVID-19 vaccination. Results Of all valid respondents (n = 903), 72.9% (n = 658) were willing to receive COVID-19 vaccination. Fear of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was the main reason for being willing to receive vaccination (76.0%), while the main reasons for not willing were the concerns about vaccine safety (54.7%) and the vaccination’s effect on antiretroviral therapy (ART) (50.6%). The most important factors influencing acceptance were the perception that vaccination is unsafe for HIV-infected people (aOR = 0.082, 95% CI = 0.024–0.282) and the poor efficacy in preventing SARS-CoV-2 infection in HIV-infected people (aOR = 0.093, 95% CI = 0.030–0.287). Other factors associated with acceptance included Zhuang ethnicity (aOR = 1.653, 95% CI = 1.109–2.465), highest education level of middle school, high school or above (aOR = 1.747, 95% CI = 1.170–2.608; aOR = 2.492, 95% CI = 1.326–4.682), and the vaccination having little effect on ART efficacy (aOR = 2.889, 95% CI = 1.378–6.059). Conclusions Acceptance rate of the COVID-19 vaccination is relatively low among PLWH compared to the general population in China, although some patients refused vaccination due to concerns about vaccine safety and vaccination affecting ART efficacy. More research is needed to investigate the impact of the COVID-19 vaccines on ART efficacy and the effectiveness in preventing SARS-CoV-2 infection among PLWH.

Marfan syndrome (MFS) is an autosomal dominant connective tissue disorder that canonically affects the ocular, skeletal, and cardiovascular system, in which aortic tear and rupture is the leading cause of death for MFS patients. Genetically, MFS is primarily associated with fibrillin-1 (FBN1) pathogenic variants. However, the disease-causing variant in approximately 10% of patients cannot be identified, partly due to some cryptic mutations that may be missed using routine exonic sequencing, such as non-coding intronic variants that affects the RNA splicing process. We present a 32-year female with typical MFS systemic presentation that reached to a clinical diagnosis according to the revised Ghent nosology. We performed whole-exome sequencing (WES) but the report failed to identify known causal variants when analyzing the exonic sequence. However, further investigation on the exon/intron boundaries of the WES report revealed a candidate intronic variant of the fibrillin 1 (FBN1) gene (c.248-3 C>G) that predicted to affect the RNA splicing process. We conducted minigene splicing analyses and demonstrated that the c.248-3 C>G variant abolished the canonical splicing site of intron 3, leading to activation of two cryptic splicing sites and causing insertion (c.248-1_248-2insAG and c.248-1_248-282ins). Our study not only characterizes an intronic variant to the mutational spectrum of the FBN1 gene in MFS and its aberrant effect on splicing, but highlights the importance to not neglect the exon/intron boundaries when reporting and assessing WES results. We point out the need of conducting functional analysis to verify the pathogenicity of intronic mutation, and the opportunity to re-consider the standard diagnostic approaches in cases of clinically diagnosed MFS with normal or variant of unknown significance genetic results.

FeO is a low-price material with high charge storage capacity, biocompatibility and other characteristics. It has been applied in the fields of catalysts, capacitors, electrodes and composite materials. However, the current method of preparing FeO needs to control the temperature and reducing atmosphere, which increase the production difficulty and cost. In this experiment, the molten salt electrolysis method was used to prepare FeO by using the NaCl-KCl molten salt system and Fe2O3 and Al2O3 as raw materials, and the influence of temperature on the preparation process was explored. The results showed that the electrolysis process of Fe2O3 to FeO is mainly divided into the following three stages: the electric double-layer charging process, Fe2O3 to Fe3O4 process and Fe3O4 to FeO process. The increase in temperature can improve the reaction speed and strengthen the electrolysis effect. The higher the temperature, the less Fe3O4 and more FeO in the sample. Through analysis, it was found that the increase in temperature will affect the theoretical voltage of the electrolytic reaction in thermodynamics, resulting in the increase in the overall potential provided by the power supply. In terms of kinetics, the increase in temperature will affect the viscosity of molten salt, so that O2− transport has better kinetic conditions.

Calcium ferrite containing aluminum (CFA) has been widely used in blast furnace production because it is an important compound that affects the quality of sinter. The influence of Al2O3 on CFA preparation process was studied by the raw material of CaO-Fe2O3-Al2O3. Diffraction of x-rays (XRD), scanning electron microscope (SEM) and electrochemical impedance spectroscopy (EIS) analysis were used to analyze the phase, micro morphology and the reducibility of the products. The results showed that CaO tended to combine more with Fe2O3 to form calcium ferrite with the increase of Fe2O3, whereas CaO tended to combine more with Al2O3 to form calcium aluminate with the content of Al2O3 above 45%. The micro morphology of sintered samples had a stable sintering skeleton structure due to the existence of calcium ferrite. Calcium ferrite was distributed between different particles in flakes, whereas calcium aluminate was attached to the Al2O3 particle surface. The large amount of calcium aluminate inhibited the emergence of calcium ferrite, and it had an adverse impact on the reducibility of sinter and the preparation of CFA.

The reduction of Fe2O3-Al2O3 is one of the important reactions in the resource utilization of iron-containing oxide waste. Fe2O3-Al2O3 was electro-deoxidized in the NaCl-KCl system by molten salt electrolysis to prepare FeO/Al2O3. The effect of the Fe2O3 content on the electro-deoxidation reaction process was studied. The results show that under the conditions of 850 °C, 2.3 V, and electro-deoxidation for 4 h, FeO/Al2O3 could be obtained by controlling the content of Fe2O3. The deoxidation process was divided into three stages: electric double layer charging, Fe2O3 electro-deoxidation to Fe3O4, and Fe3O4 electro-deoxidation to FeO. With the increase in the Fe2O3 content, the deoxidation reaction rate increased, and the low-valence iron oxide particles obtained by electro-deoxidation became larger. The mechanism of the influence of Fe2O3 on the electro-deoxygenation process was determined by analyzing the experimental results. The increase in the Fe2O3 content increased the concentration of activated molecules in the system, while it reduced the resistance of electro-deoxidation. The migration of active particles in the cathode was smoother, which increased the percentage of deoxygenation of activated molecules, thereby shortening the process of the deoxidation reaction.

The special working condition of shore power cable is more likely to form a crack air gap in insulating medium, which will cause gap discharge. The continuous gap discharge will cause local temperature rising and stress concentrating, which will lead to cable insulation deterioration. The electro-thermal-stress coupling method, in this paper, is used to establish the finite element model of the shore power cable. The electric, temperature and stress field distribution for the shore power cable with a crack air gap in the insulating medium is also studied, and the correctness of temperature and stress field distribution is verified by experiments. In addition, this paper investigated the variation law of the ampacity for shore power cable under different discharge energy. The results show that the maximum electric field is equal to the electric field intensity (36.1 kV/cm) at the inner edge of the insulating medium when the gap length d = 2 mm and that the temperature and stress of the cable are quadratic with load current, linear with the gap discharge energy. The research results of this paper have an engineering significance for monitoring shore power cables. [ABSTRACT FROM AUTHOR]

Various techniques have proven to be effective for treating articular cartilage defect of the knee joint, but knowledge regarding which method is best still remains uncertain. Osteochondral autologous transplantation (OAT) provides hyaline or hyaline-like repair for articular defects, whereas microfracture (MF) provides fibrocartilage repair tissue. To compare the OAT with MF procedure for the treatment of articular cartilage defect, we present an update of previous meta-analysis of randomized controlled trials.We searched for the published results of relevant trials. Then, we pooled the outcome measures of the included trials for analysis. The outcome measures assessed in this study included the number of patients who reached excellent or good results, the patients returning to the activity, the International Cartilage Repair Society (ICRS) scores, the failure rate, and the osteoarthritis rate. Six studies and 294 patients were identified as eligible for data extraction and meta-analysis. The pooled result showed that there was no significant difference in the excellent or good results (relative risks [RRs], 1.27; 95% confidence intervals [CIs], 0.95 to 1.70; p  = 0.11) and the rate of osteoarthritis (RRs, 0.64; 95% CIs, 0.37 to 1.13; p  = 0.12). There were significant differences between the two groups in the scores of ICRS (mean differences [MDs], 12.51; 95% CIs, 10.55 to 14.47; p  = 0.00001), the patients returning to activity (RRs, 2.04; 95% CIs, 1.36 to 3.07; p  = 0.0006), and in the failure rate (RRs, 0.23; 95% CIs, 0.11 to 0.49; p  = 0.0001). OAT has more advantages compared with MF procedure in referring to the index of return to activity, the scores of ICRS, and the rate of failure. However, the limitations restrict the generalizability of this study, and larger, sufficiently powered studies are necessary to evaluate the efficiency of OAT compared with MF procedure in the future., Competing Interests: None., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)