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Rotational near-field photolithography exposes photoresists by exciting surface plasmon polaritons to realize nanopatterns with ultrahigh-resolution beyond the diffraction limit. This feature enables broad application prospects in the micro-nanomanufacturing field. The lithography flight head, carrying a plasmonic lens (PL), with an approximately 10 nm spacer from the substrate, is the core of the system for effective etching. This paper investigates the flight state of a PL-loaded lithography head on the air film, based on computational fluid dynamics analysis. We found that the influence of the PL on the flight height produces an edge effect. This means that a PL fabricated on the edge region can significantly affect the flight height of the head. By processing the PL at a distance of 10 μm from the edge of the slider tail block, a steady 37 nm linewidth depth pattern was finally realized, using a rotational near-field photolithography system. [ABSTRACT FROM AUTHOR]

Increasing evidence suggests that an exaggerated maternal systemic inflammatofrery response may play a central role in the pathogenesis of preeclampsia (PE). Considering the growing evidence on microRNAs (miRNAs) and tissue-specific regulators of gene expression, we investigated the potential association of miR-210 and forkhead box p3 (Foxp3) in preeclamptic patients. Serum levels of the cytokines interleukin (IL)-6, IL-10, IL-17, and transforming grown factor-β1 were detected with ELISA. Reverse-transcription-quantitative polymerase chain reaction was performed to detect mRNA expression for maternal placenta retinoic acid-related orphan receptor C, Foxp3 and miRNA (miR)-210. Foxp3 protein expression was evaluated by western blot analysis. Serum levels of cytokines IL-10 were significantly lower in preeclamptic patients than in normal pregnant women. mRNA expression of Foxp3 was significantly lower in placenta of PE. mRNA expression of miR-210 was significantly increased in PE. Results of western blot analysis indicated that Foxp3 protein expression was lower in PE than in normal pregnant women. Our data suggest that PE manifests as a decreased number of regulatory T cells (Tregs), which regulate maternal tolerance of the fetus. In placenta from women with PE, compared with normal pregnant women, mRNA expression of Foxp3 was significantly decreased, and expression of miR-210 was significantly increased. [ABSTRACT FROM AUTHOR]

Histone deacetylase 1 (HDAC1) is known to participate in the molecular etiology of polycystic ovary syndrome (PCOS). However, its role in granulosa cell (GC) pyroptosis remains unclear. This study sought to investigate the mechanism of HDAC1 in PCOS-induced GC pyroptosis through histone modification. Clinical serum samples and the general data of study subjects were collected. PCOS mouse models were established using dehydroepiandrosterone and cell models were established in HGL5 cells using dihydrotestosterone. Expressions of HDAC1, H19, miR-29a-3p, and NLR family pyrin domain containing 3 (NLRP3) and pyroptosis-related proteins and levels of hormones and inflammatory cytokines were determined. Ovarian damage was observed by hematoxylin-eosin staining. Functional rescue experiments were conducted to verify the role of H19/miR-29a-3p/NLRP3 in GC pyroptosis in PCOS. HDAC1 and miR-29a-3p were downregulated whereas H19 and NLRP3 were upregulated in PCOS. HDAC1 upregulation attenuated ovarian damage and hormone disorders in PCOS mice and suppressed pyroptosis in ovarian tissues and HGL5 cells. HDAC1 inhibited H3K9ac on the H19 promoter and H19 competitively bound to miR-29a-3p to improve NLRP3 expression. Overexpressed H19 or NLRP3 or inhibited miR-29a-3p reversed the inhibition of GC pyroptosis by HDAC1 upregulation. Overall, HDAC1 suppressed GC pyroptosis in PCOS through deacetylation to regulate the H19/miR-29a-3p/NLRP3 axis. • HDAC1 is downregulated in the serum of PCOS patients. • HDAC1 overexpression alleviates the symptoms of PCOS mice and GCs pyroptosis in vitro. • HDAC1 inhibits H3K9ac in the H19 promoter to repress H19 expression. • H19 competitively binds to miR-29a-3p to promote NLRP3 expression. • Overexpressed H19/NLRP3 or inhibited miR-29a-3p facilitates GCs pyroptosis. [ABSTRACT FROM AUTHOR]

Aims This study explores the plant growth-promoting effect (PGPE) and potential mechanisms of the arsenic (As)-resistant bacterium Flavobacterium sp. A9 (A9 hereafter). Methods and results The influences of A9 on the growth of Arabidopsis thaliana , lettuce, and Brassica napus under As(V) stress were investigated. Additionally, a metabolome analysis was conducted to unravel the underlying mechanisms that facilitate PGPE. Results revealed that A9 significantly enhanced the fresh weight of Arabidopsis seedlings by 62.6%–135.4% under As(V) stress. A9 significantly increased root length (19.4%), phosphorus (25.28%), chlorophyll content (59%), pod number (24.42%), and weight (18.88%), while decreasing As content (48.33%, P  ≤ .05) and oxidative stress of Arabidopsis. It also significantly promoted the growth of lettuce and B. napus under As(V) stress. A9 demonstrated the capability to produce ≥31 beneficial substances contributing to plant growth promotion (e.g. gibberellic acid), stress tolerance (e.g. thiamine), and reduced As accumulation (e.g. siderophores). Conclusions A9 significantly promoted the plant growth under As stress and decreased As accumulation by decreasing oxidative stress and releasing beneficial compounds. [ABSTRACT FROM AUTHOR]

The apoptosis of foam cells leads to instability of atherosclerotic plaques. This study was designed to explore the protective role of CTRP9 in foam cell apoptosis. In our experiment, CTRP9 alleviated foam cell apoptosis. Meanwhile, CTRP9 upregulated the expression of proteins important for cholesterol efflux, such as LXRα, CYP27A1, ABCG1 and ABCA1, and improved cholesterol efflux in foam cells. Moreover, CTRP9 inhibited Wnt3a and β-catenin expression and β-catenin nuclear translocation in foam cells. In addition, adenovirus overexpression of Wnt3a abolished the effect of CTRP9 on macrophage apoptosis. Mechanistically, the AMPK inhibitor abolished the effect of CTRP9 on foam cell apoptosis, and downregulation of AdipoR1 by siRNA abrogated the activation of AMPK and the effect of CTRP9 on foam cell apoptosis. We concluded that CTRP9 achieved these protective effects on foam cells through the AdipoR1/AMPK pathway. • CTRP9 alleviates foam cells apoptosis by enhancing cholesterol efflux. • CTRP9 upregulated ABCA1 expression through Wnt/β-catenin pathway. • The effects of CTRP9 on Wnt/β-catenin pathway mediated by AdipoR1/AMPK. [ABSTRACT FROM AUTHOR]

Objective: The volume based procurement (VBP) program in China was initiated in 2022. The cost‐effectiveness of robotic arm assisted total knee arthroplasty is yet uncertain after the initiation of the program. The objective of the study was to investigate the cost‐effectiveness of robotic arm‐assisted total knee arthroplasty and the influence of the VBP program to its cost‐effectiveness in China. Methods: The study was a Markov model‐based cost‐effectiveness study. Cases of primary total knee arthroplasty from January 2019 to December 2021 were included retrospectively. A Markov model was developed to simulate patients with advanced knee osteoarthritis. Manual and robotic arm‐assisted total knee arthroplasties were compared for cost‐effectiveness before and after the engagement of the VBP program in China. Probability and sensitivity analysis were conducted. Results: Robotic arm‐assisted total knee arthroplasty showed better recovery and lower revision rates before and after initiation of the VBP program. Robotic arm‐based TKA was superior to manual total knee arthroplasty, with an increased effectiveness of 0.26 (16.87 vs 16.61) before and 0.52 (16.96 vs 16.43) after the application of Volume‐based procurement, respectively. The procedure is more cost‐effective in the new procurement system (17.13 vs 16.89). Costs of manual or robotic arm‐assisted TKA were the most sensitive parameters in our model. Conclusion: Based on previous and current medical charging systems in China, robotic arm‐assisted total knee arthroplasty is a more cost‐effective procedure compared to traditional manual total knee arthroplasty. As the volume‐based procurement VBP program shows, the procedure can be more cost‐effective. [ABSTRACT FROM AUTHOR]

In response to the challenges associated with the difficulty of obtaining critical well control parameters, particularly bottom-hole pressure, during a well blowout fire, a comprehensive computational fluid dynamics (CFD) model for analyzing well blowout fires is developed based on fluid mechanics and combustion theory, considering factors such as gas composition, pressure, wellhead diameter, wind speed, and temperature, and is validated by published experiment date. Then, a CFD simulation database is constructed by conducting a sensitivity analysis of the flame height to investigate the correlations among flow field, operating conditions and flame parameters. Subsequently, an approach incorporates an AutoEncoder (AE) to reduce the dimensionality of the highly correlated raw data, and a Bayesian Optimization-based Radial Basis Function Network (BO-RBFN) to explore the inherent patterns within the established CFD dataset and then establishes a fuzzy relation between immeasurable wellhead flow velocity and well blowout fires operating parameters, achieving an accurate prediction of wellhead flow velocity. Furthermore, utilizing the wellhead gas velocity and the calculated wellhead pressure as the initial conditions, the bottom hole pressure during blowout fire is inversed based on wellbore temperature and pressure model. As a result of this study, a model integrating numerical model, databases, intelligent algorithms is developed for determining bottom-hole pressure in the presence of a blowout fire. And the proposed deep learning-based approach demonstrated exceptional accuracy in predicting wellhead gas flow velocity, with an average absolute difference of less than 2% between validation set and test set. In addition, as the ambient temperature, wellhead pressure, and wellhead diameter increase, the height of the blowout flame increases. In contrast, as the gas temperature and wind speed increase, the height of the blowout flame gradually decreases. Notably, only marginal changes in flame height resulted from alterations in gas composition. This study can quantitatively reveal the cause of well blowout and evaluate the severity of well blowout, and have practical significance in guiding the design and execution of subsequent rescue operations for uncontrolled blowouts fires. • A novel method is developed for determining bottom-hole pressure under well blowout fire. • An accurate prediction of wellhead flow velocity is achieved based on intelligence algorithms. • A comprehensive CFD model of well blowout flame is developed. [ABSTRACT FROM AUTHOR]

Purposes: Due to the morphological diversity of deformities, technical difficulties, improperly designed components, and so on, THA remains a challenging task in dysplastic hips, especially in highly dislocated hips. The purpose of this study was to comprehensively evaluate the clinical outcomes of robot-assisted THA in patients with DDH through a large cohort study, including the precision of acetabular cup positioning, indicators of inflammatory response, indicators of muscle damage, and complications. Methods: We retrospectively analyzed patients with DDH who underwent THA in our prospectively constructed joint registry between August 2018 and August 2022. Finally, 147 manual THAs and 147 robotic-assisted THAs were included in the final analysis. Patient demographics, indicators of inflammation, indicators of muscle damage, operative time, Harris hip scores (HHS), and forgotten joint score (FJS) were recorded for analysis. The precision of the positioning of the acetabular component was assessed with plain radiographs. Results: In the Crowe II/III groups, the reconstructed center of rotation (COR) in the robotic-assisted group was closer to the anatomical COR with less variation than the manual group (absolute horizontal distances of COR 3.5 ± 2.8 vs. 5.4 ± 4.9 mm, p < 0.05; absolute vertical distances of COR 6.4 ± 4.1 vs. 11.7 ± 8.2 mm, p = 0.001). For all Crowe subtypes, the robotic-assisted THA significantly increased the proportion of acetabular cups located in the safety zone within 5° (all p < 0.05). Interleukin-6 and creatine kinase levels were slightly lower and significantly different in the robotic-assisted group at three days postoperatively (all p < 0.05). Conclusions: Compared to the manual technique, the robot-assisted technique improved the precision and reproducibility of acetabular component positioning, particularly in DDH patients with Crowe types II/III. The robotic-assisted technique did not increase operative time, bleeding, complications, or revision rates, and had a slighter early inflammatory response and muscle damage. [ABSTRACT FROM AUTHOR]

Rotational near-field photolithography uses one or an array of plasmonic lenses to directly pattern features on a rotating substrate that is coated with a very sensitive photoresist. Critical for this method is its limited etching depth. We investigate and demonstrate that the depth-of-field of the so-obtained nanopatterns is determined by both the refractive index and the thickness of the air/photoresist multi-dielectric layer. Using the transfer-matrix theory, the bounded air/photoresist dielectric layer refracts the light at the interface, which causes the constructive interference of surface plasmon polaritons (SPPs) to be confined. The wavelength of the SPPs decreases with increasing photoresist thickness. Both the simulation and experiment indicate that high depth-of-field nanostructures can be obtained by optimizing the resonance wavelength of SPPs due to the response of the system. Combining this with high-speed rotational near-field photolithography technology, we find that nanostructures with four times the depth-of-field compared with the previous off-resonance system can be obtained using organic photoresists with this optimization. [ABSTRACT FROM AUTHOR]

Objective: Blood pressure (BP) fluctuation has been demonstrated to be closely associated with stroke. However, at present, no attention is paid to the BP fluctuation following total knee arthroplasty (TKA). The aim of this study is to investigate what is BP fluctuation patterns in stroke and transient ischemic attack (TIA) patients after primary TKA, compare clinical characteristics among different BP fluctuation patterns and determine whether it could predict the occurrence of a 90‐day stroke. Methods: A retrospective study was conducted from February 1, 2011 to February 15, 2021. Stroke or TIA patients within 90 days after TKA were included. Data from a hospitalization management system were analyzed, including demographics, smoking status, comorbidities, medications, surgical variables, and 90‐day stroke, mortality, and readmission rates. BP fluctuation patterns were defined based on the average BP in the first 3 days after TKA. A logistic regression analysis model was used to identify risk factors for 90‐day stroke or TIA following TKA. Results: Of the 1687 patients who underwent primary TKA, 4.0% (68/1687) experienced a 90‐day stroke or TIA. A total of 63 patients met the inclusion criteria, with an average age of 67.5 years and 55.6% (35/63) female. The number of stroke or TIA patients in each BP fluctuation pattern (T1–T5) was 6 (9.5%), 5 (7.9%), 4 (6.3%), 13 (20.6%), and 35 (55.6%) respectively. Patients with a T5 pattern tended to be older and had a greater reduction in average systolic blood pressure (SBP) 3 days after surgery compared to other patterns. The T5 pattern was associated with a higher occurrence of stroke and a lower occurrence of TIA. Patients with a T5 pattern also had a longer length of stay within 90 days following TKA. After adjusting for confounding factors, average SBP fluctuation ≥40 mmHg and the T5 pattern of BP fluctuation remained risk factors for 90‐day stroke or TIA after TKA. Conclusion: BP fluctuation patterns in the early postoperative period are associated with 90‐day stroke and TIA following primary TKA. [ABSTRACT FROM AUTHOR]

Purpose. The purpose of this study was to establish the finite element analysis (FEA) model of acetabular bone defect reconstructed by 3D printed Ti6Al4V augment and TM augment and further to analyze the stress distribution and clinical safety of augments, screws, and bones. Methods. The FEA model of acetabular bone defect reconstructed by 3D printed Ti6Al4V augment was established by the CT data of a patient with Paprosky IIIA defect. The von Mises stresses of augments, screws, and bones were analyzed by a single-legged stance loading applied in 3 increments (500 N, 2000 N, and 3000 N). Results. The peak von Mises stresses under the maximal loading in the 3D printed augments, screws, and cortical bone were less than the yield strength of the corresponding component. However, the peak stress in the bone was greater than the yield strength of cancellous bone under walking or jogging loading. And under the same loading, the peak compressive and shear stresses in bone contact with TM augment were larger than these with 3D printed augment. Conclusions. The FEA results show that all the components will be intact under single-legged standing. However, partial cancellous bone contacted with 3D printed augment and screws will lose efficacy under walking or jogging load. So we recommend that patients can stand under full bearing, but can not walk or jog immediately after surgery. [ABSTRACT FROM AUTHOR]

Background: Periprosthetic joint infection is a serious complication after total joint arthroplasty. Despite that alpha-defensin was used as diagnostic test in the 2018 ICM (international consensus meeting) criteria, its position in the PJI diagnostic pipeline was controversial. Therefore, we performed a retrospective pilot study to identify whether synovial fluid alpha-defensin test was necessary when corresponding synovial fluid analysis (WBC count, PMN% and LE tests) was performed. Methods: Between May 2015 and October 2018, a total of 90 suspected PJI patients who underwent revisions after TJA were included in this study. Based on the 2018 ICM criteria, the interobserver agreements between preoperative diagnostic results and postoperative diagnostic results and the interobserver reliability between preoperative diagnostic results and postoperative diagnostic results with or without synovial fluid alpha-defensin tests were calculated. After that, the ROC analysis, and the direct cost-effectiveness of adding alpha-defensin was performed. Results: There were 48,16 and 26 patients in the PJI group, inconclusive group and non-PJI group, respectively. Adding the alpha-defensin tests into 2018 ICM criteria can't change the preoperative diagnostic results, postoperative diagnostic results, and the concordance between preoperative and postoperative diagnostic results. Moreover, the Risk–benefit Ratio is over 90 per changed decision and the direct cost-effectiveness of alpha-defensin was more than $8370($93*90) per case. Conclusions: Alpha-defensin assay exhibit high sensitivity and specificity for PJI detection as a standalone test based on the 2018 ICM criteria. However, the additional order of Alpha-defensin can't offer additional evidence for PJI diagnosis when corresponding synovial fluid analysis was performed (synovial fluid WBC count, PMN% and LE strip tests). Evidence level: Level II, Diagnostic study. [ABSTRACT FROM AUTHOR]

Aims: Periprosthetic joint infection (PJI) is one of the most serious complications after total joint arthroplasty (TJA) but the characterization of the periprosthetic environment microbiome after TJA remains unknown. Here, we performed a prospective study based on metagenomic next-generation sequencing to explore the periprosthetic microbiota in patients with suspected PJI. Methods: We recruited 28 patients with culture-positive PJI, 14 patients with culture-negative PJI, and 35 patients without PJI, which was followed by joint aspiration, untargeted metagenomic next-generation sequencing (mNGS), and bioinformatics analysis. Our results showed that the periprosthetic environment microbiome was significantly different between the PJI group and the non-PJI group. Then, we built a "typing system" for the periprosthetic microbiota based on the RandomForest Model. After that, the 'typing system' was verified externally. Results: We found the periprosthetic microbiota can be classified into four types generally: "Staphylococcus type," "Pseudomonas type," "Escherichia type," and "Cutibacterium type." Importantly, these four types of microbiotas had different clinical signatures, and the patients with the former two microbiota types showed obvious inflammatory responses compared to the latter ones. Based on the 2014 Musculoskeletal Infection Society (MSIS) criteria, clinical PJI was more likely to be confirmed when the former two types were encountered. In addition, the Staphylococcus spp. with compositional changes were correlated with C-reactive protein levels, the erythrocyte sedimentation rate, and the synovial fluid white blood cell count and granulocyte percentage. Conclusions: Our study shed light on the characterization of the periprosthetic environment microbiome in patients after TJA. Based on the RandomForest model, we established a basic "typing system" for the microbiota in the periprosthetic environment. This work can provide a reference for future studies about the characterization of periprosthetic microbiota in periprosthetic joint infection patients. [ABSTRACT FROM AUTHOR]

Objective: Periprosthetic joint infection (PJI) caused by non‐tubercular mycobacteria (NTM) is uncommon but catastrophic. However, conclusive clinical data on PJI caused by NTM are lacking. In this case series and systematic review, the clinical manifestations, diagnosis, and management of NTM PJI are summarized and analyzed. Methods: From 2012 to 2020, we retrospectively analyzed consecutive PJI cases caused by NTM in our institution. A literature review was also conducted from January 2000 to December 2021, utilizing the PubMed, MEDLINE, Cochrane Library, and EMBASE databases to identify all reported NTM‐induced PJI cases. The clinical characteristics, demographics, pathogen identification, treatment protocols, and prognosis of NTM PJI were summarized and analyzed. Results: In this retrospective analysis, seven patients infected with NTM following total joint arthroplasty at our institution were included, including six cases of PJI caused by NTM and one case of septic arthritis (SA) caused by NTM. There were six men and one woman, and their average age was 62.3 years. The average interval between TJA and PJI onset was 4 months. The preoperative serological markers, including the mean ESR (51 mm/h), CRP (4.0 mg/dL), fibrinogen (5.7 g/L), and D‐dimer (1.1 g/L), were increased. Six patients underwent staged revision surgery, and one patient with SA received antibiotic‐loaded bone cement beads to treat the infection. After an average of 33 months of observation following surgical intervention, none of the patients showed any symptoms of infection recurrence. From 2000 to 2021, 68 patients with NTM PJI were found in 39 studies in the published literature. Reinfections occurred within 1 year after arthroplasty in more than half (53.2%) of the patients. M. fortuitum and M. abscesses were the most prevalent rapidly growing mycobacteria (RGM) in all PJI patients, whereas Mycobacterium avium intracellulare (MAC) was the most prevalent slowly growing mycobacterium (SGM). The corresponding antibiotics were amikacin and ethambutol. The rate of culture‐negative without specific clinical symptoms was as high as 36.4% (12/33), while 45% (18/40) utilized additional diagnostic techniques such as NGS. A final clinical follow‐up record was available for 59 patients (86.7%; mean follow‐up period, 29 months), and 10.1% of patients failed to respond to treatment. Conclusion: Orthopaedic surgeons should consider NTM in patients with negative routine cultures who are at risk for Mycobacterium infection. Treatment options rely on the accurate result of microbiologic identification and drug sensitivity testing, and to achieve this, it may be necessary to send multiple culture specimens, extend the culture time, and change the culture medium. Every effort should be made to identify NTM and its various subtypes through modern diagnostic tools if necessary. [ABSTRACT FROM AUTHOR]

Purpose: To assess the efficiency of [68 Ga]Ga-DOTA-FAPI-04 in diagnosing periprosthetic hip joint infection and establish a diagnostic standard of clinical significance based on uptake pattern. Methods: [68 Ga]Ga-DOTA-FAPI-04 PET/CT was performed in patients with symptomatic hip arthroplasty from December 2019 to July 2022. The reference standard was based on the 2018 Evidence-Based and Validation Criteria. Two diagnostic criteria, SUVmax and uptake pattern, were used to diagnose PJI. Meanwhile, original data were imported into IKT-snap to draw the view of interest, A.K. was used to extract features of clinical cases, and unsupervised clustering analysis was applied according to the groups. Results: A total of 103 patients were included, 28 of whom had PJI. The area under the curve of SUVmax was 0.898, which was better than that of all of the serological tests. The cutoff value of SUVmax was 7.53, and the sensitivity and specificity were 100 and 72%, respectively. The sensitivity, specificity and accuracy of the uptake pattern were 100, 93.1 and 95%, respectively. In radiomics analysis, the features of PJI were significantly different from those of aseptic failure. Conclusion: The efficiency of [68 Ga]Ga-DOTA-FAPI-04 PET/CT in diagnosing PJI showed promising results, and the diagnostic criteria of the uptake pattern were more clinically instructive. Radiomics also showed certain application prospects in the field of PJI. Trial registration number: Trial registration: ChiCTR2000041204. Registered 24 September 2019. [ABSTRACT FROM AUTHOR]

Background: To develop and assess the performance of machine learning (ML) models based on magnetic resonance imaging (MRI) radiomics analysis for knee osteoarthritis (KOA) diagnosis. Methods: This retrospective study analysed 148 consecutive patients (72 with KOA and 76 without) with available MRI image data, where radiomics features in cartilage portions were extracted and then filtered. Intraclass correlation coefficient (ICC) was calculated to quantify the reproducibility of features, and a threshold of 0.8 was set. The training and validation cohorts consisted of 117 and 31 cases, respectively. Least absolute shrinkage and selection operator (LASSO) regression method was employed for feature selection. The ML classifiers were logistic regression (LR), K-nearest neighbour (KNN) and support vector machine (SVM). In each algorithm, ten models derived from all available planes of three joint compartments and their various combinations were, respectively, constructed for comparative analysis. The performance of classifiers was mainly evaluated and compared by receiver operating characteristic (ROC) analysis. Results: All models achieved satisfying performances, especially the Final model, where accuracy and area under ROC curve (AUC) of LR classifier were 0.968, 0.983 (0.957–1.000, 95% CI) in the validation cohort, and 0.940, 0.984 (0.969–0.995, 95% CI) in the training cohort, respectively. Conclusion: The MRI radiomics analysis represented promising performance in noninvasive and preoperative KOA diagnosis, especially when considering all available planes of all three compartments of knee joints. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to report on the use of Robotic-assisted total joint arthroplasty (RA-TJA) in China as well as the experience and expectations of Chinese doctors regarding this technology. Method: A self-administered questionnaire was used to assess the current status of RA-TJA in China, the practical experience and suggestions for improvement of the technology by joint surgeons who have performed RA-TJA, and the interest and expectations of orthopaedic surgeons who have not used RA-TJA. The questionnaire was administered to all the physicians of the Chinese Association of Orthopedic Surgeons (CAOS). Result: A total of 372 qualified questionnaires were generated, among which 28% (n = 104) of the respondents had performed RA-TJA, among those who had performed RA-TJA. When asked how helpful the joint replacement robot was actually/expected to be, there was no significant difference between the expected and actual experience of nonusers and users (p ≥ 0.05); the biggest disadvantage of the current development of RA-TJA was perceived as additional charges to the patient by those who had used it, while those who had not used it perceived it as a limitation of their hospital, both of which were significant differences. Most respondents in both groups (used: 94.2%; not used: 91.4%) were confident in the clinical development of the joint replacement robot. Conclusion: This survey provides cross-sectional data on the current status of Chinese joint surgeons using or not using robots in their daily clinical practice. Improving surgical precision was the consensus of most respondents, while high surgical costs and limitations of hospital conditions were barriers to its development in China. [ABSTRACT FROM AUTHOR]

BACKGROUND: Periprosthetic joint infection (PJI) is one of the worst complications following total joint arthroplasty (TJA). Unfortunately, effective prevention strategies to reduce the burden of PJI have not been fully determined in hip replacement patients with fracture and non-fracture. OBJECTIVE: This study aimed to analyze and compare the demographic characteristics, microbiological profiles and antibiotic resistance of PJI after hip replacement between patients with fracture and non-fracture. METHODS: We retrospectively analyzed the data of 132 patients who treated PJI. There were divided into two groups: non-fracture group (64 patients infected after hip replacement for fracture) and non-fracture group (68 patients infected after hip replacement for non-fracture). Microorganisms were obtained from the synovial fluid and infected necrotic tissue in the joint capsule, medullary cavity, or acetabulum in all patients, and microbiological profiles and antibiotic resistance were evaluated. RESULTS: Coagulase-negative staphylococci (CoNS) were the most common pathogenic microorganisms in all patients. Methicillin-resistant Staphylococcus (MRS) accounted for 25% in all pathogenic microbes. Staphylococci showed high drug resistance rates to clindamycin, levofloxacin, and all of the first- and second-generation cephalosporins. MRS isolates in non-fracture group had higher drug resistance rates to clindamycin and levofloxacin than than those in fracture group. Gram-negative bacilli (GNB) showed high drug resistance rates to Aztreonam, gentamicin and all of the third- and fourth-generation cephalosporins. Furthermore, GNB isolates in the non-fracture group showed higher resistance rates to gentamicin and all of the third- and fourth-generation cephalosporins. CONCLUSIONS: MRS isolates in the non-fracture group showed higher drug resistance rates to clindamycin and levofloxacin, and GNB isolates in non-fracture group showed higher drug resistance rates to gentamicin and all of the third- and fourth-generation cephalosporins. [ABSTRACT FROM AUTHOR]

Background: As one of the major diagnostic criteria in Musculoskeletal Infection Society, the microbiological diagnosis of periprosthetic joint infection (PJI) performed by analyzing periprosthetic tissue culture is recommended. The goal of this study was to determine if methylene blue (MB) has antibacterial effects that might interfere with microbial culture in vitro. Methods: Eight isolates of reference strains of Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus hominis, Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Streptococcus pyogenes, and Candida albicans were incubated appropriately on blood agar, China blue agar, or Sabouraud’s agar plates at 35 ℃. (Streptococci were cultured in a CO2-rich atmosphere.) Each bacterial suspension was formed by 50-fold dilution before the test MB was added. For each strain, bacterial suspension was divided into 3 groups (5 samples each) exposed either MB 0.1%, MB 0.05% or sterile non-bacteriostatic 0.45% saline. The antimicrobial property of MB was determined by measuring the bacterial density on agar plates incubated for 24 h and comparing it with controls unexposed to MB. Results: Exposure to MB 0.1% or MB 0.05% negatively affected microbial viability in vitro. Of the diluted form of MB exposure, reference strains of S. hominis and A. baumannii resulted in fewer colony-forming units compared with the sterile saline control. MB concentration was significantly negatively correlated with CFU counts of S. hominis and A. baumannii strains. The antibacterial property of MB 0.1% or MB 0.05% appears to affect the ability to culture the organism in in vitro assays. Conclusion: MB 0.1% or MB 0.05% has strong antimicrobial activities against some commonly encountered bacterial strains in PJI in vitro. To further evaluate its potential antibacterial usefulness in clinical applications, the next studies are needed to assess the ability of MB to affect the ability to culture the pathogens in vivo, especially in periprosthetic tissue. [ABSTRACT FROM AUTHOR]

β-ionone is a volatile metabolite of Microcystis aeruginosa that is toxic to aquatic organisms. Using Daphnia sinensis as model, our present study found that β-ionone could significantly reduce heart rate and feeding rate, and induce intestinal emptying. Transcriptomic analysis showed that β-ionone could significantly inhibit the expression of acetylcholinesterase (AchE) mRNA, while metabolomics further revealed that β-ionone could significantly increase the level of acetylcholine (Ach) in D. sinensis. These results indicated that β-ionone might act as an AchE inhibitor, resulting in an increase in Ach levels. To test this hypothesis, both in vivo and in vitro experiments demonstrated that β-ionone could significantly reduce AchE activity. Furthermore, the inhibitory effects of β-ionone on heart rate and feeding rate could be blocked by the M-type Ach receptor (mAchR) blocker. These findings confirm that β-ionone is a novel AchE inhibitor. β-ionone could inhibit the activity of AchE, which in turn resulted in an increase of Ach in D. sinensis. Consequently, elevated levels of Ach could suppress the heart rate and feeding rate of D. sinensis by activating the mAchR, while concurrently accelerating the rate of intestinal emptying by stimulating intestinal peristalsis, thereby obstructing the digestion of algae within the intestinal tract. [Display omitted] • M. aeruginosa caused a wide range of physiological abnormalities in D. sinensis. • M. aeruginosa has the capability to release considerable quantities of β-ionone. • β-ionone could significantly inhibit the grazing of D. sinensis. • β-ionone is confirmed to be a novel acetylcholinesterase inhibitor. [ABSTRACT FROM AUTHOR]

Objective: Robot‐assisted surgery has been promoted worldwide in recent years. The development of a domestic orthopaedic robot and its clinical application are therefore of great significance. This study aimed to compare the early clinical and radiographic outcomes of domestic robot‐assisted total knee arthroplasty (RA‐TKA) with conventional manual total knee arthroplasty (CM‐TKA). Methods: A total of 77 patients who underwent primary single‐sided TKA from June to December 2020 were prospectively enrolled; resulting in the inclusion of 72 patients. The patients were randomly divided into the RA‐TKA group (37 cases, with TKA being assisted by the Yuanhua Orthopaedic Robotic System) and the CM‐TKA group (35 cases, with TKA being performed using conventional tools). Knee function was evaluated by the knee range of motion (ROM), the American Knee Society Score (KSS), and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Postoperative radiographic results were evaluated by full‐length weight‐bearing X‐rays of the lower limb and anteroposterior and lateral X‐rays of the knee were obtained preoperatively and at 90 days postoperative. The operative duration, blood loss, postoperative knee function, radiographic outcomes, and incidence of complications were compared by Student's t‐test, Mann–Whitney U test, or chi‐square test. Serum levels of inflammatory markers before the operation and 1, 3, and 30 days after the operation were recorded and compared between the two groups. Results: The operation was significantly longer in the RA‐TKA group than in the CM‐TKA group (154.3 vs 115.2 min, p < 0.001). There was no significant difference in blood loss (933 vs 863 ml, p = 0.519) between the two groups. The knee ROM, KSS, and WOMAC were significantly improved in both groups 90 days after the operation compared with before the operation (p < 0.05), but there were no significant differences between the two groups (p > 0.05). The incidence of postoperative deep vein thrombosis was not statistically different between the two groups. In the radiographic findings at 90 days postoperatively we found the frequency of lateral tibial component (LTC) angle outliers was significantly lower in the RA‐TKA group (3.0% vs 29.4%, p = 0.003). The neutrophil‐to‐lymphocyte ratio (NLR) was significantly lower in the RA‐TKA group than in the CM‐TKA group on day 1 after surgery (9.9 vs 12.7, p = 0.024). Conclusions: RA‐TKA requires more time than CM‐TKA, which may be related to the learning curve and intraoperative registration. The short‐term postoperative knee functional outcomes had no differences between the two groups, and RA‐TKA improved the accuracy of tibial component alignment. Further follow‐up studies are required to investigate the long‐term outcomes. [ABSTRACT FROM AUTHOR]

• CTRP9 enhanced NLRP3 inflammasome activation in peritoneal macrophages. • NOX2/ROS participated in CTRP9-mediated NLRP3 inflammasome activation. • CTRP9-KO mice were resistant to LPS infection with lessened NLRP3 inflammasome. • CTRP9 is a potential target for the intervention of inflammasome-driven diseases. The NLRP3 inflammasome plays a vital role in inflammation by increasing the maturation of interleukin-1β (IL-1β) and promoting pyroptosis. Given that C1q/tumour necrosis factor-related protein-9 (CTRP9) has been shown to be involved in diverse inflammatory diseases, we sought to assess the underlying impact of CTRP9 on NLRP3 inflammasome activation. In vitro, macrophages isolated from murine peritonea were stimulated with exogenous CTRP9, followed by lipopolysaccharide (LPS) and adenosine 5′-triphosphate (ATP). We demonstrated that CTRP9 markedly augmented the activation of the NLRP3 inflammasome, as shown by increased mature IL-1β secretion, triggering ASC speck formation and promoting pyroptosis. Mechanistically, CTRP9 increased the levels of NADPH oxidase 2 (NOX2)-derived reactive oxygen species (ROS). Suppressing ROS with N-acetylcysteine (NAC) or interfering with NOX2 by small interfering RNA weakened the promoting effect of CTRP9 on the NLRP3 inflammasome. Furthermore, NLRP3 inflammasome activation, pyroptosis and secretion of mature IL-1β were significantly decreased in macrophages from CTRP9-KO mice compared to those from WT mice with the same treatment. In vivo, we established a sepsis model by intraperitoneal injection of LPS into WT and CTRP9-KO mice. CTRP9 knockout improved the survival rates of the septic mice and attenuated NLRP3 inflammasome-mediated inflammation. In conclusion, our study indicates that CTRP9 aggravates LPS-induced inflammation by promoting NLRP3 inflammasome activation via the NOX2/ROS pathway. CTRP9 could be a promising target for NLRP3 inflammasome-driven inflammatory diseases. [ABSTRACT FROM AUTHOR]

Objective: To report the long‐term outcomes of total hip arthroplasty (THA) with fourth‐generation ceramic‐on‐ceramic (CoC) bearing in patients with ankylosing spondylitis (AS). Methods: We retrospectively identified 180 primary THAs performed in 110 patients with AS, including 100 (90.9%) men and 10 women (9.1%), from 2009 to 2011.The mean age of the patients at surgery was 33 years (range, 16 to 65 years). Cementless prostheses with fourth‐generation CoC bearings were used in all patients. Survivorship of the implants and postoperative complications were calculated. Functional improvement was assessed by the hip flexion‐extension range of motion (ROM) and Harris hip score (HHS). A special noise assessment questionnaire was performed at the last follow‐up. The cumulative incidence of noise was calculated by the Kaplan–Meier method with 95% confidence intervals (CIs). Clinical characteristics and functional outcomes were compared in the hips with noise to those without noise. Results: The mean follow‐up was 11 years (range, 10 to 12 years), and survivorship of the implants was 99.4% at the most recent follow‐up. The complications included dislocation (one hip, 0.6%), periprosthetic joint infection (one hip, 0.6%), mild to moderate pain (five hips, 2.8%), heterotopic ossification (12 hips, 6.7%), and noise (52 hips, 28.9%). The flexion‐extension ROM improved significantly with a median from 10° (range, 0 ~ 130°) to 100° (30 ~ 130°) after THA (p < 0.001), and the HHS increased significantly from 41 ± 20 to 90 ± 8 (p < 0.001). The cumulative incidence of noise at 0.5, 5, and 10 years was 6.1% (95% CI, 2.6 ~ 9.6), 16.7% (95% CI, 11.2 ~ 22.1), and 28.9% (95% CI, 22.2 ~ 35.5), respectively, and that of squeaking at 0.5, 5, and 10 years was 4.4% (95% CI, 1.4 ~ 7.4), 13.3% (95% CI, 8.4 ~ 18.3), and 23.9% (95% CI, 17.6 ~ 30.1), respectively. None of the patients with noise generation in the hip reported it affecting daily activities or causing dissatisfaction. No differences in age, sex, BMI, disease duration, bilateral THA, the frequency of bony ankylosis, the proportion of using a 36‐mm‐diameter femoral head, pre/postoperative flexion‐extension ROM, or pre/postoperative HHS were found between hips with noise and those without noise (p > 0.05). Conclusion: THAs with fourth‐generation CoC bearings exhibit excellent long‐term survival and clinical outcomes in patients with AS, with a very low dislocation rate. The incidence of noise associated with CoC bearings in THA performed in patients increases over time, but it does not affect postoperative hip function or daily activities. [ABSTRACT FROM AUTHOR]

Objective: To introduce the surgical technique of reconstruction of Paprosky type III acetabular defects by 3D printed porous augments. Methods: First, CT scans of pelvis were obtained to establish the 3D reconstruction model of 3D printed porous augment. Then, a nylon pelvis model was printed to simulate operation with the surgeons. At this time, the augment was designed and modified according to the surgeon's suggestions and the 3D printing principles. Eighteen patients with Paprosky type III acetabular defects receiving reconstructive surgery by 3D printed porous augments were included in current study. Their data, including general information, intra‐operative findings, imaging results, functional scores, and complications were retrospectively analyzed. Results: The mean follow‐up time lasted 33.3 ± 2.0 (24–56) months. The average limb‐length discrepancy (LLD) was 31.7 ± 4.2 (3–59) mm preoperatively, 7.7 ± 1.4 (1–21) mm postoperatively (P < 0.0001), and 7.5 ± 1.2 (0–18) mm at the latest follow‐up. The mean vertical position of hip center of rotation (HCOR) from the interteardrop line changed from preoperative 50.7 ± 3.9 (23.3–75.3) mm to postoperative 22.9 ± 1.9 (10.1–40.3) mm (P < 0.0001), with the latest follow‐up revealing an HCOR of 22.3 ± 1.7 (11.0–40.5) mm. Follow‐up study showed that no hip had radiolucencies and radiological loosening of the acetabular components and augment. The average Harris hip score (HHS) improved from 40.3 ± 4.5 (10.5–71) before operation to 88.4 ± 1.9 (75–97) at the last follow‐up (P < 0.0001). Moreover, follow‐up exhibited that no periprosthetic joint infection, hip dislocation, fracture, and re‐revision occurred. Conclusion: Surgical treatment of Paprosky type III acetabular defect with 3D printed porous augment was simple, achieved good match between porous augment and the defect bone surface and the acetabular component, ideally restored LLD and HCOR after operation, significantly improved HHS and attained good early clinical outcomes. It is a promising personalized solution for patients with severe acetabular bone defect. [ABSTRACT FROM AUTHOR]

Background: Most patients with displaced femoral neck fractures are treated by THA and hemiarthroplasty, but it remains uncertain which if either is associated with better function and lower risks of complications. Questions/purposes: We performed a meta-analysis of randomized controlled trials (RCTs) to determine whether THA was associated with lower rates of reoperations, mortality, complications, and better function compared with hemiarthroplasty. Methods: We searched the PubMed, Embase, Chinese Biomedicine Literature, and Cochrane Register of Controlled Trials databases and identified 12 RCTs (including a total of 1320 patients) for meta-analysis. Risk ratios (RRs) and weighted mean differences (WMDs) from each trial were pooled using random-effects or fixed-effects models depending on the heterogeneity of the included studies. Results: THA was associated with a lower risk of subsequent reoperations compared with hemiarthroplasty (RR = 0.53; 95% CI, 0.34-0.84). There was no difference in mortality between patients undergoing THA and hemiarthroplasty (RR = 0.81; 95% CI, 0.60-1.09). For complications, there was a higher risk of dislocation in patients undergoing THA (RR = 1.99; 95% CI, 1.26-3.15), but there were no differences in local infections (RR = 1.60; 95% CI, 0.74-3.46) and general complications (RR = 1.15; 95% CI, 0.91-1.45). Patients with THA had higher Harris hip scores at 1 year (WMD = 3.81; 95% CI, 0.87-6.74) and at 3 or 4 years (WMD = 10.07; 95% CI, 6.92-13.21). Conclusions: Despite more dislocations, THA can benefit patients with displaced femoral neck fractures with a lower reoperation rate and higher functional scores. [ABSTRACT FROM AUTHOR]

Objective: To explore the possibility of obtaining more accurate information from routine blood tests for the diagnosis of periprosthetic joint infection (PJI). Methods: This is a retrospective study. Between 2017 and 2018, a total of 246 patients who underwent total hip or knee revision surgery were included in this study. There were 146 females and 100 males, and the mean age of the patients was 62.1 ± 12.75 years. Laboratory parameters erythrocyte sedimentation rate (ESR), C‐reactive protein (CRP), D‐dimer, plasma fibrinogen, serum white blood cell (WBC), and calculable ratio markers were collected. Based on leukocytes (monocyte count, neutrophil count, lymphocyte count), platelet count, and mean platelet volume Inflammation‐related ratio markers were calculated, which including monocyte to lymphocyte ratio (MLR), neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), and platelet to mean platelet volume ratio (PMR). Follow‐up of all studied cases for at least 1 year. The diagnostic value of the markers based on the receiver operating characteristic (ROC) analysis. The most optimal combinations of blood markers were selected by the prediction models. Statistical analyses and prediction models were performed using R software. Results: Of the 246 patients, 125 were diagnosed with PJI and 121 with aseptic loosening. A higher rate of patients underwent revision surgery due to hip prosthesis loosening in the aseptic loosening group (74.4%) compared to the PJI group (45.6%, P < 0.001). ROC curves showed that the area under the curve (AUC) for classical markers, fibrinogen was 0.853 (95% confidence interval [CI], 0.805–0.901), ESR was 0.836 (95% CI, 0.785–0.887) and CRP was 0.825 (95% CI, 0.773–0.878). Followed by the PMR, PLR, NLR and MLR, which showed promising diagnostic performance with AUCs of 0.791, 0.785, 0.736, and 0.733. The AUCs of the ratio markers were higher than those of D‐dimer (0.691;95% CI, 0.6243–0.7584) and serum WBC (0.622; 95% CI, 0.552–0.691). After the predictive model calculation, AUC was up to 0.923 (95% CI, 0.891–0.951) when plasma fibrinogen combined with MLR and PMR and interpreted excellent discriminatory capacity with a sensitivity of 86.40% and a specificity of 84.17%. The new combination significantly increases the accuracy and reliability of the diagnosis of PJI (P < 0.001). The AUC increased to 0.899 (95% CI, 0.861–0.931; P = 0.007) and 0.916 (95% CI, 0.880–0.946; P < 0.001), followed by CRP and ESR, respectively. All plasma fibrinogen, ESR, and CRP combined with both PMR and MLR achieved the highest specificity (89.17%) and PPV (85.34%). Conclusion: The diagnostic performance greatly improved when plasma fibrinogen, ESR, and CRP combined with ratio markers. [ABSTRACT FROM AUTHOR]

Here, we performed N6-methyladenosine (m6A) RNA sequencing to determine the circRNA m6A methylation changes in the placentas during the pathogenesis of preeclampsia (PE). We verified the expression of the circRNA circPAPPA2 using quantitative reverse transcription-PCR. An invasion assay was carried out to identify the role of circPAPPA2 in the development of PE. Mechanistically, we investigated the cause of the altered m6A modification of circPAPPA2 through overexpression and knockdown cell experiments, RNA immunoprecipitation, fluorescence in situ hybridization and RNA stability experiments. We found that increases in m6A-modified circRNAs are prevalent in PE placentas and that the main changes in methylation occur in the 3'UTR and near the start codon, implicating the involvement of these changes in PE development. We also found that the levels of circPAPPA2 are decreased but that m6A modification is augmented. Furthermore, we discovered that methyltransferase‑like 14 (METTL14) increases the level of circPAPPA2 m6A methylation and that insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) maintains circPAPPA2 stability. Decreases in IGF2BP3 levels lead to declines in circPAPPA2 levels. In summary, we provide a new vision and strategy for the study of PE pathology and report that placental circRNA m6A modification appears to be an important regulatory mechanism. [ABSTRACT FROM AUTHOR]

Background: The relevance between the presence of a sinus tract and the failure risk after debridement, antibiotics and implant retention (DAIR) for periprosthetic joint infection (PJI) after hip or knee arthroplasty is still unclear. This study aimed to compare the success rate of DAIR between patients with or without a sinus tract and to explore the possible risk factors for failure after DAIR in patients with a sinus tract.Methods: Consecutive DAIR cases for PJI after hip or knee arthroplasty between January 2009 and June 2019 with a minimum 1-year follow-up in two tertiary joint arthroplasty centers were included. Patients were classified into the sinus tract group and the non-sinus tract group according to the presence of a sinus tract. The success rate after DAIR were compared using Kaplan-Meier survival analysis. Potential risk factors for failure in the sinus group were also explored.Results: One hundred seven patients were included. At a median 4.4 years of follow-up, 19 of 52 (36.5%) cases failed in the sinus tract group, while 15 of 55 (27.3%) cases failed in the non-sinus tract group. The 1-year and 5-year cumulative success rates were 71.2% (95% confidence interval (CI): 59.8-84.6%) and 56.8% (95% CI: 42.6-75.7%) in the sinus tract group, respectively, which were similar to the counterparts in the non-sinus tract group (P = 0.214). Among patients with a sinus tract, DAIR with the exchange of modular components showed a higher success rate (75.8% versus 47.4%, P = 0.038).Conclusions: The presence of a sinus tract does not affect the success rate of DAIR. Modular component exchange in DAIR was proposed for patients with a sinus tract for an improved infection control rate. [ABSTRACT FROM AUTHOR]

Aims: Preoperative aspiration culture and intraoperative cultures play pivotal roles in periprosthetic joint infection (PJI) diagnosis and pathogen identification. But the discordance between preoperative aspiration culture and intraoperative synovial fluid culture remains unknown. We aim to determine (1) the discordance between preoperative and intraoperative synovial fluid (SF) culture and. (2) compared to intraoperative synovial fluid cultures, the sensitivity of preoperative aspiration fluid culture. Then the following question is tried to be answered: Are intraoperative synovial fluid re-cultures necessary if the preoperative aspiration culture is positive?Materials and Methods: Between 2015 and 2019, 187 PJI patients managed with surgeries were included in this study. Compared to intraoperative synovial fluid culture, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of preoperative aspiration culture were calculated. Then, the discordance between preoperative aspiration culture and intraoperative SF culture was analyzed.Results: The sensitivity of preoperative aspiration culture was 81.29% compared to intraoperative synovial fluid cultures. Concordance was identified in 147 PJI (78.61%) patients and culture discordance occurred in 40 patients (21.39%). In these discordant PJI patients, 24 patients (60%) were polymicrobial and no intraoperative synovial fluid culture growth was found in 16 PJI cases (40%). Preoperative monomicrobial staphylococcus results had a sensitivity of and a specificity of 80.43% and 83.16%, respectively. Preoperative polymicrobial results had the lowest sensitivity.Conclusions: The intraoperative synovial fluid re-cultures are necessary if the preoperative aspiration culture is positive and the discordance between preoperative aspiration culture and intraoperative synovial fluid culture should be noted especially when Streptococcus spp. and more than one pathogen was revealed by preoperative aspiration culture.Level Of Evidence: Level III. [ABSTRACT FROM AUTHOR]

Background: Periprosthetic joint infection is a serious complication after total joint arthroplasty and polymicrobial PJI which compose a subtype of PJI often indicate worse outcomes compared to monomicrobial periprosthetic joint infection. However, a literature review suggested that there were limited number studies evaluating the risk factors of polymicrobial PJI.Materials and Methods: Between 2015 January and 2019 December, a total of 64 polymicrobial PJI patients and 158 monomicrobial PJI patients in a tertiary center were included in this study and corresponding medical records were scrutinized. The diagnosis of PJI was based on 2014 MSIS criteria. Logistic regression was used to identify the association between various variables and polymicrobial PJI and ROC curve was used to identify their efficiency.Results: The prevalence of polymicrobial PJI is 28.3% in our cohorts. After adjusting for the presence of sinus, previous and knee infection, isolation of enterococci (OR, 3.025; 95%CI (1.277,7.164) p = 0.012), infection with atypical organisms (OR, 5.032;95%CI: (1.470,17.229) p = 0.01), infection with gram-negative organisms (OR, 2.255; 95%CI (1.011,5.031) p = 0.047), isolation of streptococcus spp. (OR, 6; 95%CI (2.094,17.194) p = 0.001), and infection with CNS (OfR, 2.183;95%CI (1.148,4.152) p = 0.017) were risk factors of polymicrobial PJI compared to monomicrobial PJI. However, knee infection is related to a decreased risk of polymicrobial PJI with an adjusted OR = 0.479 (p = 0.023).Conclusion: This study demonstrated that the prevalence of polymicrobial PJI is 28.3% in PJI patients. Moreover, the presence of sinus tract and previous joint revisions were risk factors for identifying different bacterial species in the intraoperative specimens. Therefore, in these PJI cases, it is necessary to examine multiple specimens of both intraoperative tissue and synovial fluid for increasing the detection rate and obtaining resistance information. [ABSTRACT FROM AUTHOR]

β-cyclocitral is one of the major compounds in cyanobacterial volatile organic compound (VOCs) and can poison other aquatic organisms. To investigate the effect of β-cyclocitral on cyanobacterial-grazer interactions, Daphnia sinensis was fed Microcystis aeruginosa and exposed to β-cyclocitral. Our present study demonstrated that M. aeruginosa could significantly inhibit D. sinensis grazing. And the grazing inhibition by Microcystis aeruginosa results from the suppression of feeding rate, heart rate, thoracic limb activity and swimming speed of D. sinensis. In addition, M. aeruginosa could also induce intestinal peristalsis and emptying in D. sinensis. Interestingly, our present study found that the exposure to β-cyclocitral could mimic a range of phenotypes induced by M. aeruginosa in D. sinensis. These results suggested that M. aeruginosa could release β-cyclocitral to inhibit Daphnia grazing. To further examine the toxic mechanism of β-cyclocitral in Daphnia , several in vivo and in vitro experiments displayed that β-cyclocitral was a novel inhibitor of acetylcholinesterase (AChE). It could induce the accumulation of acetylcholine (ACh) by inhibiting AchE activity in D. sinensis. High level of endogenous Ach could inhibit feeding rate and induce intestinal peristalsis and emptying in D. sinensis. [Display omitted] • Ingestion of M. aeruginosa resulted in physiological abnormalities in D. sinensis. • 0.1 μM β-cyclocitral induced similar physiological abnormalities. • β-cyclocitral is proposed to be a new acetylcholinesterase inhibitor. • β-cyclocitral could help M. aeruginosa to resist D. sinensis grazing. [ABSTRACT FROM AUTHOR]

Aims: Periprosthetic joint infection (PJI) is a serious complication of total joint arthroplasty. We performed a retrospective cohort study to evaluate (1) the change of coagulation profile in two-staged arthroplasty patients and (2) the relationship between coagulation profile and the outcomes of reimplantation. Method: Between January 2011 and December 2018, a total of 202 PJI patients who were operated on with two-staged arthroplasty were included in this study initially. This study continued for 2 years and the corresponding medical records were scrutinized to establish the diagnosis of PJI based on the 2014 MSIS criteria. The coagulation profile was recorded at two designed points, (1) preresection and (2) preimplantation. The difference of coagulation profile between preresection and preimplantation was evaluated. Receiver operating characteristic curves (ROC) were used to evaluate the diagnostic efficiency of the coagulation profile and change of coagulation profile for predicting persistent infection before reimplantation. Results: The levels of APTT, INR, platelet count, PT, TT, and plasma fibrinogen before spacer implantation were significantly higher than before reimplantation. No significant difference was detected in the levels of D-dimer, ACT, and AT3 between the two groups. The AUC of the combined coagulation profile and the change of combined coagulation profile for predicting persistent infection before reimplantation was 0.667 (95% CI 0.511, 0.823) and 0.667 (95% CI 0.526, 0.808), respectively. Conclusion: The coagulation profile before preresection is different from before preimplantation in two-staged arthroplasty and the coagulation markers may play a role in predicting infection eradication before reimplantation when two-stage arthroplasty is performed. Level of evidence: Level III, diagnostic study. [ABSTRACT FROM AUTHOR]

Background and Purpose. This study established an animal model of the acetabular bone defect in swine and evaluated the bone ingrowth, biomechanics, and matching degree of the individualized three-dimensional (3D) printed porous augment. Methods. As an acetabular bone defect model created in Bama miniswine, an augment individually fabricated by 3D print technique with Ti6Al4V powders was implanted to repair the defect. Nine swine were divided into three groups, including the immediate biomechanics group, 12-week biomechanics group, and 12-week histological group. The inner structural parameters of the 3D printed porous augment were measured by scanning electron microscopy (SEM), including porosity, pore size, and trabecular diameter. The matching degree between the postoperative augment and the designed augment was assessed by CT scanning and 3D reconstruction. In addition, biomechanical properties, such as stiffness, compressive strength, and the elastic modulus of the 3D printed porous augment, were measured by means of a mechanical testing machine. Moreover, bone ingrowth and implant osseointegration were histomorphometrically assessed. Results. In terms of the inner structural parameters of the 3D printed porous augment, the porosity was 55.48 ± 0.61 % , pore size 319.23 ± 25.05 μ m , and trabecular diameter 240.10 ± 23.50 μ m. Biomechanically, the stiffness was 21464.60 ± 1091.69 N / mm , compressive strength 231.10 ± 11.77 MPa , and elastic modulus 5.35 ± 0.23 GPa , respectively. Furthermore, the matching extent between the postoperative augment and the designed one was up to 91.40 ± 2.83 %. Besides, the maximal shear strength of the 3D printed augment was 929.46 ± 295.99 N immediately after implantation, whereas the strength was 1521.93 ± 98.38 N 12 weeks after surgery (p = 0.0302). The bone mineral apposition rate (μm per day) 12 weeks post operation was 3.77 ± 0.93 μ m / d. The percentage bone volume of new bone was 22.30 ± 4.51 % 12 weeks after surgery. Conclusion. The 3D printed porous Ti6Al4V augment designed in this study was well biocompatible with bone tissue, possessed proper biomechanical features, and was anatomically well matched with the defect bone. Therefore, the 3D printed porous Ti6Al4V augment possesses great potential as an alternative for individualized treatment of severe acetabular bone defects. [ABSTRACT FROM AUTHOR]

Background. The purpose of this study was to establish the finite element analysis (FEA) model of acetabular bone defect in Crowe type II or III developmental dysplasia of the hip (DDH), which could evaluate the stability of the acetabular cup with different types of bone defects, different diameters of femoral ceramic heads, and the use of screws and analyze the stress distribution of screws. Methods. The FEA model was based on the CT scan of a female patient without any acetabular bone defect. The model of acetabular bone defect in total hip arthroplasty for Crowe II or III DDH was made by the increasing superolateral bone defect area of the acetabular cup. Point A was located in the most medial part of the acetabular bone defect. A 52 mm PINNACLE cup with POROCOAT Porous coating was implanted, and two screws (the lengths were 25 mm and 40 mm) were implanted to fix the acetabular cup. The stability of the acetabular cup and the von Mises stress of point A and screws were analyzed by a single-legged stance loading applied in 1948 N (normal working). The different diameters of the femoral ceramic head (28 mm, 32 mm, and 36 mm) were also analyzed. Results. The von Mises stress of point A was gradually increased with the increasing uncoverage values. When the uncoverage values exceeded 24.5%, the von Mises stress of point A without screws increased significantly, leading to instability of the cup. Screws could effectively reduce the von Mises stress of point A with uncoverage values of more than 24.5%. However, the peak von Mises stress in the screws with the uncoverage values that exceeded 24.5% was considerably increased. The diameter of the femoral ceramic head had no significant effect on the von Mises stress and the stability of the acetabular cup. Conclusions. We recommend that uncoverage values of less than 24.5% with or without screw is safe for patients with Crowe II or III DDH. [ABSTRACT FROM AUTHOR]

Background: The impact of handedness on clinical outcomes was easily overlooked in hip replacement. This study aimed to find whether the component positioning and hip function were affected by the handedness in total hip arthroplasty (THA) through direct anterior approach (DAA).Methods: Total 102 patients who underwent bilateral DAA-THAs simultaneously between May 2016 and November 2018 in our institute were reviewed. All surgeries were operated by one right-handed surgeon. Their demographic, cup positioning, stem alignment, femoral stem fit, Harris hip score (HHS), intraoperative and postoperative complications were used to evaluate the role of handedness in DAA.Results: The inclination of left cups was significantly larger than that of right cups (42.61 ± 7.32 vs 39.42 ± 7.19, p = 0.000). The stem fit of left femur was significantly larger than that of right femur (84.34 ± 4.83 vs 82.81 ± 6.07, p = 0.043). No significant differences in safe zone ratio, HHS and complications between bilateral hips were found.Conclusions: A surgeon's handedness had significant impact on cup's inclination and femoral stem fit in DAA-THA. However, there were no significant differences of cup malpositioning, stem alignment, hip function scores and complications between bilateral DAA-THAs. [ABSTRACT FROM AUTHOR]

Background: The study focusing on the tissue adhesive in total knee arthroplasty (TKA) was rare. This study aimed to evaluate the clinical outcomes and economic costs of tissue adhesive when acting as the adjunct to standard incision closure in TKA.Patients and Methods: From September 2019 to November 2019, we prospectively enrolled the consecutive patients who underwent simultaneous bilateral TKA in our institute. The allocation using the tissue adhesive was done after the subcuticular suture in right knee first and another method was applied in the left knee automatically. The patients' demographics, length of stay (LOS), times of dressing changes and incision-related cost, range of motion (ROM), incision-related complications and incision evaluation scores were recorded.Results: Thirty-two patients were enrolled in this study and followed at two months after surgery. In the knees of tissue adhesive, the times of dressing change and patient scar assessment scores (PSAS) were significantly less than those standard skin closure (p=0.000; p=0.003). Although there were no significant differences of the delayed discharge, incision-related cost, ROM, incision-related complications and Vancouver scar score (VSS) between two groups, 65.6% (21/32) patients preferred the tissue adhesive and only 15.6% (5/32) patients preferred the standard incision closure.Conclusion: Tissue adhesive could effectively reduce postoperative wound drainage and improve patients' satisfaction rate with no difference in medical costs and ROM in TKA. The application of tissue adhesive and subcuticular sutures might be one safe and convenient method of skin closure in TKA.Chinese Clinical Trial Registry: ChiCTR1900025730; Registered 6 September 2019. [ABSTRACT FROM AUTHOR]

Background: Conversion of arthrodesed hips to total hip arthroplasty (THA) remains technically demanding. This study aims to evaluate the safety and efficacy of robot-assisted THA in arthrodesed hips.Methods: We retrospectively analyzed 45 ankylosing spondylitis patients with hip arthrodesis in the Chinese PLA General Hospital between August 2018 and August 2019. All surgeries were carried out by one single surgeon. The patients were followed at 3 months after surgery. Gender, body mass index, angle of hip arthrodesis, operating time, intraoperative fluoroscopic times, postoperative length of hospitalization, cup positioning, postoperative leg length discrepancy, offset discrepancy, intraoperative and postoperative complications, and postoperative Harris Hip Score were collected for all patients.Results: Twenty-two patients (35 hips) who underwent robot-assisted THA and 23 patients (37 hips) who underwent manual THA were enrolled in this study. There were no significant differences in demographics and arthrodesed angles between the two groups. The fluoroscopic times during manual THA were significantly higher than those during robot-assisted THA (2.16±1.61 vs 0.47±0.61, respectively, p=0.000). In the robotic group, the percentage of acetabular cups within the safe zone was significantly greater than in the manual group (94.29% vs 67.56%, respectively, p=0.042). For manual THA, the anteversions were significantly different between the left and right sides (21.14±7.86 vs 16.00±6.32, respectively, p=0.042); however, no such significant difference was found in robot-assisted THA.Conclusion: Compared with manual THA for arthrodesed hips, robot-assisted THA had significant advantages in improving the frequency of achieving cup positioning within the target zone with diminished radiation dose and no increase in operating time. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to examine whether surgeon handedness could affect cup positioning in manual total hip arthroplasty (THA), and whether robot could diminish or eliminate the impact of surgeon handedness on cup positioning in robot-assisted THA. Methods: Fifty-three patients who underwent bilateral robot-assisted THA and sixty-two patients who underwent bilateral manual THA between August 2018 and July 2019 in our institute were respectively analyzed in this study. When the difference between the bilateral anteversion and inclination was greater than 5°, the patient was regarded as having different cup positioning between bilateral THA. Their demographics, orientation of acetabular cup, and postoperative 3 month Harris hip score (HHS) were recorded for analysis. Results: There were no significant differences in the gender, age, BMI, diagnosis's composition, and preoperative and postoperative HHS between the robotic and manual group. Two left hips dislocated in the manual group. The anteversion of left hip was significantly larger than that of right hip (24.77 ± 10.44 vs 22.44 ± 8.67, p = 0.043) in the manual group. There were no significant differences of cup positioning between bilateral robot-assisted THA. The patients in manual group were significantly more likely to have different cup positioning between bilateral hips than those in robotic group (77% vs 45%, p = 0.000). More manual THA were located out of the target zone than robot-assisted THA (70% vs 48%, p = 0.001). Conclusions: Surgeon's handedness showed a trend towards an impact on cup positioning in manual THA and robot might help surgeon eliminate the adverse impact. However, the impact of handedness on the clinical outcomes still needs further observation. [ABSTRACT FROM AUTHOR]

Background: We aimed to present our experience of adopting tissue adhesive as adjunct to standard wound closure in total hip arthroplasty (THA) and evaluate its performance.Methods: From September 2019 to November 2019, we prospectively enrolled consecutive patients who underwent simultaneous bilateral THA in this randomized and controlled study. Standard wound closure was applied on one side of hip while additional tissue adhesive was applied on the other side at random. We collected and analyzed patients' information, including age, gender, body mass index (BMI), diagnosis, postoperative length of stay (LOS), dressing changes, wound evaluation scores, wound-related cost and complications.Results: Thirty patients with simultaneous bilateral THA were enrolled in this study. During the hospital stay, the times of dressing change in hips with tissue adhesive was significantly less than that in the other hips (p = 0.000). However, the wound-related cost in hips with tissue adhesive was significantly higher (p = 0.000). According to patients' feedback at one-month follow-up, wound evaluation of hips with tissue adhesive was significantly better than the other hips (p = 0.004). Seventeen patients preferred tissue adhesive and only five patients preferred standard wound closure.Conclusions: Tissue adhesive could significantly reduce wound drainage and increase patients' satisfaction, which can be an ideal adjunct to standard wound closure in enhanced-recovery THA.Trial Registration: Chinese Clinical Trial Registry; ChiCTR1900025730; Registered 6 September 2019. [ABSTRACT FROM AUTHOR]

Background: Trochanter valgus deformity (TVD) is a rare condition of total hip arthroplasty (THA). Femoral osteotomy could be required in correcting the deformity to implant femoral stem in severe TVD. In this study, we described one unpublished technique of reverse sleeve of S-ROM to get through the complex situation. This study aimed to summarize and evaluate its technical challenges, safety and effectiveness.Methods: From January 2006 to December 2014, we enrolled patients whose sleeves were implanted towards the great trochanter in THA with TVD. Their demographics, perioperative and postoperative information were recorded. To explore its indication, we measured and analyzed the ratio of greater trochanter/lesser trochanter (G/L ratio) and trochanter valgus angle (TVA).Results: Twelve patients (1 male and 11 female, average age 42.30 ± 10.23) had mean follow-up of 6 years. Among them, only two patients had intraoperative femoral fracture. The survivorship of femoral prosthesis was 100%. The Harris hip score (HHS) increased from preoperative 34.31 ± 14.43 to postoperative 84.12 ± 11.33. All patients' G/L ratio were larger than 1.50.Conclusions: The reverse sleeve of S-ROM was a reliable method for the patients with severe TVD, which brought satisfying clinical outcomes in mid-term follow-up. [ABSTRACT FROM AUTHOR]

Background: Diagnosing periprosthetic joint infection (PJI) requires various laboratory and clinical criteria. The purpose of this study was to explore novel biomarkers that could rapidly diagnose PJI with high accuracy.Methods: In this retrospective study of prospectively collected samples, 50 synovial fluid aspirates, 20 from the hip and 30 from the knee, were collected before surgery; 25 of the patients were diagnosed as having aseptic loosening (non-PJI) and 25, as having PJI according to the Musculoskeletal Infection Society criteria. A quadrupole orbital-trap mass spectrometry (MS) instrument was used to compare expression of proteins in patients with and without PJI. Proteins that were most efficacious for diagnosis of PJI were then determined using prediction analysis of microarray software and a random forest model. The most promising proteins were selected, and altered expression of these selected proteins was verified by ELISA (enzyme-linked immunosorbent assay) in an extended sample cohort.Results: A total of 256 proteins were significantly upregulated (≥3.0-fold) and 14 proteins were downregulated in synovial fluid of patients with PJI compared with patients without PJI. The 3 most promising proteins were lactoferrin (LTF), polymorphonuclear leukocyte serine protease 3 (PRTN3), and myeloid nuclear differentiation antigen (MNDA). When MS was used for diagnosis of PJI, the area under the curve was 0.9888 for LTF, 0.9488 for PRTN3, and 0.9632 for MNDA. ELISA results verified that LTF, MNDA, and PRTN3 were sensitive, while LTF and MNDA were specific, for diagnosis of PJI.Conclusions: This proteomic study identified a previously noted protein and 2 novel candidate proteins as promising synovial fluid biomarkers for PJI diagnosis, and they should be further validated in future clinical trials.Level Of Evidence: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Acute myocardial infarction is one of the most threatening disease in the world. In previous studies, numerous dysregulated lncRNAs exposed to ischemic reperfusion injury have been identified. In this differential lncRNAs, Gm2691 attracted our attention due to its high fold change. The aim of the study was to investigate the function and mechanism of lncRNA Gm2691 in ischemic reperfusion injury. AnaeroPack anaerobic system treated neonatal rat ventricular cardiomyocytes were used to analyze the function of lncRNA Gm2691 in vitro. Tunel, Caspase3, and inflammation markers were detected to evaluate apoptosis and inflammatory response. Rat acute myocardial infarction was performed to elucidate the function of lncRNA Gm2691 in vivo. The results showed that LncRNA Gm2691 improved the cardiac function and attenuated the inflammatory response in vivo. We also found that lncRNA Gm2691 reduced the apoptosis and improved cell survival rates in anaeroPack anaerobic system treated neonatal rat ventricular cardiomyocytes. Western blot analysis revealed that lncRNA Gm2691 decreased Akt and ERK1/2 activities, suggesting that lncRNA Gm2691 may functioned through Akt signaling pathway. We verified the function and mechanism of lncRNA Gm2691 and provide evidence that lncRNA Gm2691 may play important role in ischemic reperfusion injury, and understanding the precise role of Gm2691 will undoubtedly shed new light on the clinical treatment. [ABSTRACT FROM AUTHOR]

Flowering is a crucial process for plants that is under complex genetic control. AP1 acts as an organizer and a switch for the transition from vegetative to reproductive growth. In our previous study, we found that overexpression of BpAP1 significantly promoted the formation of male inflorescence in birch (Betula platyphlla × B. pendula). In this study, we aimed at investigating the molecular regulatory mechanism of BpAP1 during the process of male inflorescence formation in birch. We found that overexpression of BpAP1 affected the expression of many flowering-related genes, and had significant effect on B class MADS-box genes. A BpAP1-mediated gene regulatory network was constructed and B class gene BpDEF was finally predicted as a key target gene of BpAP1. Chromatin immunoprecipitation results indicated that BpAP1 could directly regulate BpDEF during the process of male inflorescence formation. Yeast one-hybrid assays and its validation in tobacco results suggested that BpAP1 regulated BpDEF via binding to a consensus DNA sequence known as CArG box. Gene function analysis of BpDEF indicated that BpDEF may function in sex-determination, and in particular specify the identity of male inflorescence in birch. Our results provide valuable clues for our understanding of the molecular mechanism of BpAP1 during the process of male inflorescence formation in birch. [ABSTRACT FROM AUTHOR]

Introduction: Sexual activity is often an important component of life. To date, no studies have examined sexual activity before and after total hip arthroplasty (THA) in male patients with ankylosing spondylitis (AS). The purpose of the current study was to evaluate the effect of THA on sexual activity and to explore the most commonly reported and comfortable coital position for male AS patients with hip involvement. Methods: Data from 31 male AS patients who underwent THA for hip involvement were retrospectively reviewed. Information from the International Index of Erectile Function (IIEF), the Harris Hip Score (HHS) and other clinical parameters was collected and monitored over time. We compared the above-mentioned parameters before surgery and 2 years after surgery and analysed the correlation between changes on the IIEF and changes in clinical parameters. Results: The domain and total scores of the IIEF, except EF, were significantly higher after surgery than were those before surgery (p < 0.05). There was a significant positive correlation between changes on the IIEF and improvement in flexion-extension range of motion (ROM), adduction-abduction ROM and HHS (p < 0.05). Most patients (26/31, 83.9%) resumed sexual activity 5–12 weeks after surgery. The pre- and postoperative distributions of the most commonly reported and comfortable position were not significantly different (p > 0.05). Conclusions: Successful THA may improve sexual activity in male AS patients with hip involvement. Changes in hip ROM show the most significant correlation with improvement in sexual activity. Resumption of sexual activity occurs within 5–12 postoperative weeks. [ABSTRACT FROM AUTHOR]

Introduction: There is growing support in the literatures that peri-operative outcomes are adversely affected by surgical case order in some certain surgical procedures. This study aimed to examine if similar phenomenon is also shared in total joint arthroplasty (TJA).Methods: A total of 6548 joints (5183 patients) treated with primary TJA by a total of five surgeons at our institution from December 2011 to December 2015 were retrospectively reviewed in this study. Demographic data, operative duration, blood loss, peri-operative adverse events, medical cost, and length of hospital stay were collected and analyzed. Logistic regression was used to determine risk factors for adverse events.Results: Of the 6548 cases in this cohort, 1643 TJAs were classified as first round cases, 1744 TJAs were second round cases, 1600 TJAs were third round cases, and 1561 TJAs were fourth or later round cases. Mean operating time was shorter in the intermediate cases (45.0 vs. 41.0 vs. 41.8 vs. 54.1 min, P < 0.01). Peri-operative arthroplastic adverse events were increased in later surgical cases (2.07% vs. 2.18% vs. 3.06% vs. 4.87%, P < 0.01). Later case order (OR = 1.40 [95% CI: 1.22-1.61], P < 0.01) was a significant risk factor of arthroplastic adverse events. Patients undergoing TJA later in the day were more likely to have longer length of stay and higher cost than earlier cases. Peri-operative systemic complications and blood loss did not significantly differ between groups.Conclusion: Surgical case order is an independent risk factor for arthroplastic adverse events in TJA. TJA procedures performed later in the day have a higher risk for arthroplastic adverse events, but not for systematic adverse events. Significantly increased operative time, higher cost, and longer LOS were noted for fourth or later TJA cases. Data in our study reveals that performing more than three TJAs within a single day may imply compromised outcomes. [ABSTRACT FROM AUTHOR]

Periprosthetic joint infection (PJI) is a catastrophic complication following total joint arthroplasty. Until now, the diagnosis of PJI is still confronted with difficulties, which is characterized by technical limitations. The question of whether sonication fluid PCR can provide high value in the diagnosis of PJI remains unanswered. This meta-analysis included 9 studies that evaluated PCR assays of sonication fluid for the diagnosis of PJI. The pooled sensitivity, specificity, Positive likelihood ratio (PLR), Negative likelihood ratio (NLR) and Diagnostic odds ratio (DOR) were 0.75 (95% confidence interval [CI], 0.71 to 0.81), 0.96 (CI, 0.94 to 0.97), 18.24 (CI, 6.07 to 54.78), 0.27 (CI, 0.20 to 0.36) and 86.97 (CI, 37.08 to 203.97), respectively. The AUC value of the SROC was 0.9244 (standard error, 0.0212). Subgroup analyses showed that use of multiplex PCR and may improve sensitivity and specificity. The results of this meta-analysis showed that PCR of fluid after sonication is reliable and of great value in PJI diagnosis. [ABSTRACT FROM AUTHOR]

Aiming to address the difficulties in predicting the collapse strength of sand control screen pipes with internal corrosion defects under the external pressure in offshore unconsolidated sandstone oil and gas reservoirs development, a parametric analysis model of a screen pipe with corrosion defects was established based on secondary development of ABAQUS by Python script, and was verified by the published experimental data. Then, the effect of corrosion defect and hole parameters on the collapse strength of the screen pipes was analyzed. Furthermore, a novel data-driven model with the gradient boosting regression tree (GBRT) method was used to explore and characterize the laws contained in the numerical simulation data based on a large volume of numerical simulation data. The results demonstrated that the proposed data-driven prediction model for the collapse strength of screen pipes exhibited a stable prediction average difference of 3.97% in the test set. And a large number of generalization practices based on data-driven prediction model indicated that corresponding corrosion parameter warning interval existed when the screen pipe design structure was determined, and when the corrosion defect size was greater than the warning interval, the collapse capacity of the screen pipe was considerably weakened. Moreover, the collapse strength was the lowest when the corrosion defect was located at the center of the screen pipe. And the collapse strength of the screen pipe gradually decreased with an increase of corrosion defects parameter and hole arrangement parameter. This study can provide a reference for evaluating the strength and establishing a safety-related warning mechanism of sand control screen pipes with corrosion defects. • A novel GBRT data-driven model was proposed to characterize the collapse pressure of the screen pipe. • Generalization practice based on data-driven model predicted corrosion parameter warning intervals of the screen pipe. • A parametric analysis had been established to investigate the collapse behavior of screen pipes with corrosion defects. [ABSTRACT FROM AUTHOR]

Background: Symptomatic chronic low back and leg pain resulting from lumbar spine degenerative disorders is highly prevalent in China, and for some patients, surgery is the final option for improvement. Several techniques for spinal non-fusion have been introduced to reduce the side-effects of fusion methods and hasten postoperative recovery. In this study, the authors have evaluated the cost-effectiveness of Dynesys posterior dynamic stabilization system (DY) compared with lumbar fusion techniques in the treatment of single-level degenerative lumbar spinal conditions.Methods: A total of 221 patients undergoing single-level elective primary surgery for degenerative lumbar pathology were included. 2-Year postoperative health outcomes of Visual Analogue Scale (VAS) for back and leg pain, Oswestry Disability Index (ODI), 36-Item Short Form Health Survey (SF-36) and EuroQol-5 Dimensions (EQ-5D) questionnaires were recorded. 2-Year back-related medical resource use, missed work, and health-state values (Quality-adjusted life-year [QALY]) were assessed. Cost-effectiveness was determined by the incremental cost per QALY gained.Results: At each follow-up point, both cohorts were associated with significant improvements in VAS scores, ODI, SF-36 scores and EQ-5D QALY scores, which persisted at the 2-year evaluation. The 2-year total mean cost per patient were significantly lower for Dynesys system ($20,150) compared to fusion techniques ($25,581, $27,862 and $27,314, respectively) (P < 0.001). Using EQ-5D, the mean cumulative 2-year QALYs gained were statistically equivalent between the four groups (0.28, 0.27, 0.30 and 0.30 units, respectively) (P = 0.74). Results indicate that patients implanted with the DY system derive lower total costs and more utility, on average, than those treated with fusion.Conclusions: The Dynesys dynamic stabilization system is cost effective compared to instrumented lumbar fusion for treatment of single-level degenerative lumbar disorders. It is not possible to state whether DY or lumbar fusion is more cost-effective after 2 years. [ABSTRACT FROM AUTHOR]

Background: Culture-negative periprosthetic joint infection (PJI) is very intractable when dealing with an infected total knee arthroplasty (TKA) patient. Two-stage revision has been proved to be a reliable solution for PJI patients. Whether it is still credible for culture-negative infected patients remains uncertain.Methods: Our group retrospectively reviewed all total knee revision patients from January 2003 to January 2014, 145 PJI patients were diagnosed as infection with the PJI diagnostic criteria and 129 patients were successfully followed. As different treating strategies were utilized, these patients were divided into culture-negative (18 cases, CN) group, culture-positive with one-stage revision group (CP1, 21 cases) and culture-positive with two-stage revision group (CP2, 87 cases) groups. The CN group and CP2 group underwent two-stage revision with antibiotic loaded cement spacers and intravenous antibiotics, CP1 group received one-stage revision. All the culture results and relevant medical records were thoroughly reviewed.Results: The mean follow-up time was 59.5 ± 32.3 months (range 12-158 months). The culture-negative rate was 14.2%. The overall infection control rate was 92.12%. Infection recurrence was observed in two cases in CP1 group (9.09%), six cases in CP2 group (6.90%) and two cases in CN group (11.1%). The reinfection rate of culture-negative patients and culture-positive patients was 7.34% and 11.1% with no significant difference (p = 0.94). No statistically difference was observed between CP2 group and CN group (p = 0.90). No Spacer fracture or dislocation was observed.Conclusion: With combined or broad spectrum antibiotics, two-stage revision showed comparable outcome when treating culture-negative infected TKA patients at five-year follow-up. [ABSTRACT FROM AUTHOR]

The objective of this study is to evaluate the differences in cardiovascular manifestations between ankylosing spondylitis (AS) patients with and without kyphosis. A retrospective review of consecutive AS patients treated at our hospital between June 2013 and June 2015 was performed. There were 122 patients who met all of the inclusion and exclusion criteria. Among these patients, there were 57 (ASK group) patients with global kyphosis (GK) > 40° and 65 (AS group) patients with GK < 40°. General information, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), electrocardiography, and echocardiography were record. ESR and CRP levels in the ASK group were significantly higher than the AS group ( P < 0.05). Fifteen patients in ASK group but 3 patients in AS group suffered from a left ventricular high voltage ( P < 0.05). Heart rate in ASK group was 83.91 ± 13.68 beats/min, and it was 73.88 ± 13.04 beats/min in AS group ( P < 0.05). The E/A ratio was 1.13 ± 0.38 in ASK group and 1.32 ± 0.49 in AS group ( P < 0.05). The mitral E-wave deceleration time and isovolumetric relaxation time were, respectively, 236.25 ± 34.26 ms and 101.86 ± 17.57 ms in ASK group, which were shorter in AS group ( P < 0.05). This study showed that AS patients with kyphosis had a statistically increased incidence of cardiovascular complications including a more rapid heart rate, left ventricular high voltage, and left ventricular diastolic dysfunction. [ABSTRACT FROM AUTHOR]