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Wear particle-induced osteolysis is a major cause of aseptic loosening, which is one of the most common reasons for total hip arthroplasty (THA) failure. Previous studies have shown that the synovial fibroblasts present in the periprosthetic membrane are important targets of wear debris during osteolysis. However, the interaction mechanisms between the wear debris and fibroblasts remain largely unknown. In the present study, we investigated the effect of ER (endoplasmic reticulum) stress induced by TiAl6V4 particles (TiPs) in human synovial fibroblasts and calvarial resorption animal models. The expression of ER stress markers, including IRE1-α, GRP78/Bip and CHOP, were determined by western blot in fibroblasts that had been treated with TiPs for various times and concentration. To address whether ER stress was involved in the expression of RANKL, the effects of ER stress blockers (including 4-PBA and TUDCA) on the expression of RANKL in TiPs-treated fibroblasts were examined by real-time PCR, western blot and ELISA. Osteoclastogenesis was assessed by tartrate resistant acid phosphatase (TRAP) staining. Our study demonstrated that ER stress markers were markedly upregulated in TiPs-treated fibroblasts. Blocking ER stress significantly reduced the TiPs-induced expression of RANKL both in vitro and in vivo. Moreover, the inhibition of ER stress ameliorated wear particle-induced osteolysis in animal models. Taken together, these results suggested that the expression of RANKL induced by TiPs was mediated by ER stress in fibroblasts. Therefore, down regulating the ER stress of fibroblasts represents a potential therapeutic approach for wear particle-induced periprosthetic osteolysis.

This paper investigates a unified theory to derive vector network analyzer calibration algorithms based on the T-matrix representation, by which means the line-reflect-match (LRM), line-reflect-match-match (LRMM), and the line-reflect-reflect-match (LRRM) calibrations are formulated. The proposed calibration theory is more general than other versions of LRM, LRMM, and LRRM in that an arbitrary known two-port device can be used as the line standard L, rather than a perfect thru or transmission line. Experimental verifications of the proposed theory using on-wafer calibrations from 0.5 GHz to 110 GHz are given.

The field of piezoresistive sensors has been undergoing a significant revolution in terms of design methodology, material technology and micromachining process. However, the temperature dependence of sensor characteristics remains a hurdle to cross. This review focuses on the issues in thermal-performance instability of piezoresistive sensors. Based on the operation fundamental, inducements to the instability are investigated in detail and correspondingly available ameliorative methods are presented. Pros and cons of each improvement approach are also summarized. Though several schemes have been proposed and put into reality with favorable achievements, the schemes featuring simple implementation and excellent compatibility with existing techniques are still emergently demanded to construct a piezoresistive sensor with excellent comprehensive performance.

Genome-wide association studies (GWAS) have recently identified KIF1B as susceptibility locus for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). To further identify novel susceptibility loci associated with HBV-related HCC and replicate the previously reported association, we performed a large three-stage GWAS in the Han Chinese population. 523,663 autosomal SNPs in 1,538 HBV-positive HCC patients and 1,465 chronic HBV carriers were genotyped for the discovery stage. Top candidate SNPs were genotyped in the initial validation samples of 2,112 HBV-positive HCC cases and 2,208 HBV carriers and then in the second validation samples of 1,021 cases and 1,491 HBV carriers. We discovered two novel associations at rs9272105 (HLA-DQA1/DRB1) on 6p21.32 (OR = 1.30, P = 1.13×10⁻¹⁹) and rs455804 (GRIK1) on 21q21.3 (OR = 0.84, P = 1.86×10⁻⁸), which were further replicated in the fourth independent sample of 1,298 cases and 1,026 controls (rs9272105: OR = 1.25, P = 1.71×10⁻⁴; rs455804: OR = 0.84, P = 6.92×10⁻³). We also revealed the associations of HLA-DRB1*0405 and 0901*0602, which could partially account for the association at rs9272105. The association at rs455804 implicates GRIK1 as a novel susceptibility gene for HBV-related HCC, suggesting the involvement of glutamate signaling in the development of HBV-related HCC.

A controllable metal–insulator transition (MIT) of VO _2 has been highly desired due to its huge potential applications in memory storage, smart windows or optical switching devices. Recently, interfacial strain engineering has been recognized as an effective approach to tuning the MIT of epitaxial VO _2 films. However, the strain-involved structural evolution during the MIT process is still not clear, which prevents comprehensively understanding and utilizing interfacial strain engineering in VO _2 films. In this work, we have systematically studied the epitaxial VO _2 thick films grown on TiO _2 (001) single crystal substrate and the structural transition at the boundary of MIT region. By using in situ temperature-dependent high-resolution x-ray diffractions, a tetragonal-like (‘T-like’) to ‘rutile’ structural phase transition is identified during the MIT process. The room-temperature crystal phase of epitaxial VO _2 /TiO _2 (001) thick film is clarified to be tetragonal-like, neither strained-rutile phase nor monoclinic phase. The calculated atomic structure of this T-like phase VO _2 resembles that of the M1 phase VO _2 , which has been verified by their similar Raman spectra. More, the crystal lattices of the coexisted phases in the MIT region were revealed in detail. The current findings will not only show some clues on the MIT mechanism study from the structural point of view, but also favor the interface engineering assisted VO _2 -based devices and applications in the future.

Recurrent miscarriage (RM) is a distressing pregnancy complication. While the etiology of RM remains unclear, growing evidence has indicated the relevance of trophoblast impairment to the pathogenesis of RM. PR-SET7 is the sole enzyme catalyzing monomethylation of H4K20 (H4K20me1) and has been implicated in many pathophysiological processes. However, how PR-SET7 functions in trophoblasts and its relevance to RM remain unknown. Here, we found that trophoblast-specific loss of Pr-set7 in mice led to defective trophoblasts, resulting in early embryonic loss. Mechanistic analysis revealed that PR-SET7 deficiency in trophoblasts derepressed endogenous retroviruses (ERVs), leading to double-stranded RNA stress and subsequent viral mimicry, which drove overwhelming interferon response and necroptosis. Further examination discovered that H4K20me1 and H4K20me3 mediated the inhibition of cell-intrinsic expression of ERVs. Importantly, dysregulation of PR-SET7 expression and the corresponding aberrant epigenetic modifications were observed in the placentas of RM. Collectively, our results demonstrate that PR-SET7 acts as an epigenetic transcriptional modulator essential for repressing ERVs in trophoblasts, ensuring normal pregnancy and fetal survival, which sheds new light on potential epigenetic causes contributing to RM. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy and safety of abdominal aortic balloon for pregnant women with placenta increta or percreta (PIP). Methods: Retrospective analysis of the parameters containing estimated blood loss, red cell suspension (RCS) transfusion volume, hysterectomy, surgery time, postoperative hospital days, neonatal status and complications between the two groups. Results: The patients with preoperative abdominal aortic balloon occlusion (AABO) had significant reduction in blood loss volume, red cell suspension transfusion volume and plasma transfusion volume compared to patients without balloon. Similarly, the surgery time and hysterectomy were obviously reduced in the AABO group. However, there were no difference in the Apgar scores and neonatal complications between the two groups, indicating that the abdominal aortic balloon has little adverse effect on the newborns. Conclusion: AABO plays dramatic roles on reducing blood loss volume and blood transfusion volume and it is also a safe and effective technology providing new insight into the therapy of patient with PIP. Synopsis: Preoperative abdominal aortic balloon occlusion (AABO), as a new intravascular interventional therapy, is safe and effective in patients with placenta increta or percreta. [ABSTRACT FROM AUTHOR]

Introduction: There is an urgent need to find novel stable cell-free fetal (cff-) RNA in the maternal circulation to facilitate the advance of non-invasive prenatal testing (NIPT) to more effectively avoid birth defects.Methods: CircRNA microarray was used to detect the cff-circRNA in plasma.Results: There were cff-circRNAs from the fetus in the peripheral blood of pregnant women and they persisted even until at least 24 h after delivery. In addition, we found that cff-circRNA might have a specific expression pattern in gestational disease.Conclusions: We demonstrated the presence of cff-circRNA in the maternal circulation, which may shed new light on the development of NIPT. [ABSTRACT FROM AUTHOR]

Wiskott-Aldrich syndrome protein family verprolin-homologous protein 2 (WAVE2) is a protein that mediates actin cyto-skeletal reorganization and lamellipodia protrusion formation, which are required for cell migration and invasion. The primary purpose of this study was to determine whether there is an association between reactive oxygen species (ROS) and WAVE2 in pre-eclampsia, and whether WAVE2 expression in trophoblast cells is vulnerable to oxidative stress. This study observed excessive generation of ROS and decreased expression of WAVE2 in pre-eclamptic placentas compared with normotensive controls. Moreover, there was a significant negative correlation between ROS and WAVE2 protein in pre-eclamptic placenta (P< 0.001). An in-vitro model of hypoxia--reoxygenation (H/R) was used to imitate oxidative stress in placental trophoblasts, and it was found that the expression of WAVE2 protein in trophoblasts was decreased after H/R treatment. Additionally, compared with normoxia, decreased cell proliferation, higher cell apoptosis and attenuated cell migration and invasion were detected in trophoblasts exposed to H/R. In conclusion, the findings strongly suggest that excessive oxidative stress can decrease WAVE2 expression in trophoblasts and that the decreased expression of WAVE2 in trophoblast cells may be involved in the development of pre-eclampsia. [ABSTRACT FROM AUTHOR]

Background: Prior prelabor cesarean delivery (CD) was associated with an increase in the risk of placenta previa (PP) in a second delivery, whether it may impact postpartum hemorrhage (PPH) independent of abnormal placentation. This study aimed to assess the risk of PPH stratified by abnormal placentation following a first CD before the onset of labor (prelabor) or intrapartum CD. Methods: This multicenter, historical cohort study involved singleton, pregnant women at 28 weeks of gestation or greater with a CD history between January 2017 and December 2017 in 11 public tertiary hospitals within 7 provinces of China. PPH was analyzed in the subsequent pregnancy between women with prior prelabor CD and women with intrapartum CD. Furthermore, PPH was analyzed in pregnant women stratified by complications with PP alone [without placenta accreta spectrum (PAS) disorders], complications with PP and PAS, complications with PAS alone (without PP), and normal placentation. We performed multivariate logistic regression to calculate adjusted odds ratios (aOR) and 95% CI controlling for predefined covariates. Results: Out of 10,833 pregnant women, 1,197 (11%) women had a history of intrapartum CD and 9,636 (89%) women had a history of prelabor CD. Prior prelabor CD increased the risk of PP (aOR 1.91, 95% CI 1.40-2.60), PAS (aOR 1.68, 95% CI 1.11-2.24), and PPH (aOR 1.33, 95% CI 1.02-1.75) in a subsequent pregnancy. After stratification by complications with PP alone, PP and PAS, PAS alone, and normal placentation, prior prelabor CD only increased the risk of PPH (aOR 3.34, 95% CI 1.35-8.23) in a subsequent pregnancy complicated with PP and PAS. Conclusion: Compared to intrapartum CD, prior prelabor CD increased the risk of PPH in a subsequent pregnancy only when complicated by PP and PAS., 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 © 2021 Shilei, Lizi, Yulian, Yingyu, Lijun, Minshan, Baoying, Jinping, Yinli, Shaoshuai, Xiaoyan, Ling, Yangyu, Xianlan, Qiying, Hongbo, Suiwen, Lanzhen, Hongtian, Jingsi, Zhijian, Lili and Dunjin.)