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Background: Deep vein thrombosis (DVT) is a common and serious risk in elderly patients with knee osteoarthritis (OA), making preoperative detection crucial. Despite this, identifying OA patients at high risk for preoperative DVT and appropriately targeting them for venous ultrasound screening remains a challenge. There is limited research-based evidence on the risk factors for preoperative DVT in elderly patients with end-stage OA. We examined the incidence of and risk factors for preoperative DVT in elderly patients with end-stage OA scheduled for total knee arthroplasty. Methods: We retrospectively analyzed the demographic data (age, sex, body mass index, current smoking, alcohol consumption, walking status, and Barthel index score), medical history, and laboratory test indices of 1411 patients with end-stage OA aged ≥ 60 years scheduled for total knee arthroplasty from January 2015 to December 2018. Risk factors for preoperative DVT were evaluated by univariate and multivariate logistic analyses. Receiver operating characteristic analysis was performed to determine optimal cut-off values. Results: The incidence of preoperative DVT was 4.5% (63 of 1411 patients). Seven independent risk factors were correlated with preoperative DVT in the multivariate logistic regression: age (odds ratio [OR], 1.073; P = 0.002), D-dimer concentration (OR, 1.173; P = 0.003), hyperlipidemia (OR, 2.038; P = 0.045), atrial fibrillation (OR, 4.004; P = 0.033), chronic renal failure (OR, 6.732; P = 0.008), chronic obstructive pulmonary disease (COPD) (OR, 8.721; P = 0.001), and walking status (wheelchair) (OR, 2.697; P = 0.002). The optimal cut-off values for predicting preoperative DVT were 0.585 µg/mL for the D-dimer concentration (area under the curve [AUC], 0.769; P < 0.001) and 72.5 years for age (AUC, 0.668; P < 0.001). Conclusion: Among elderly patients with end-stage OA, venous ultrasonography to rule out DVT risk should be prioritized in those with a high D-dimer concentration (> 0.585 µg/mL), high age (> 72.5 years), hyperlipidemia, atrial fibrillation, chronic renal failure, COPD, and walking status (wheelchair). [ABSTRACT FROM AUTHOR]

The thermal compression experiment of GH984G18 alloy was carried out using thermal-mechanical testing machines Gleeble3800. Based on the stress-strain curves obtained from the experiments, the processing maps of the GH984G18 alloy were established according to the dynamic materials model (DMM), then the hot working process window of alloy was built, and the influence of temperature and strain on the dynamic recrystallization of the experimental alloy was also analyzed. The results show that when the strain is small(ε≤0.2), the optimum deformation temperature is in the temperature range of 1030-1090℃ and strain rate range of 0.01-0.18s-1; with the increase of strain(ε≥0.3), the optimum deformation temperature moves to the high temperature range of 1180-1200℃ and strain rate range of 0.056-0.25s-1; and at the strain rate of 1s-1, dynamic recrystallization does not occur and dynamic recovery dominates when the temperature is lower than 900℃; and partial dynamic recrystallization occurs at the temperature of 1000℃ and the strain of 30%; and then the complete dynamic recrystallization occurs at the temperature of 1000℃ and strain of 60%.

A multi-dimensional earthquake isolation and mitigation device for long-span reticulated structures is a type of newly invented passive control device. In order to acquire the earthquake isolation and mitigation effect of the new devices on long-span reticulated structures under horizontal excitations, the pseudo-dynamic tests for a 1:3 modeled long-span reticulated structure with a size of 3 m × 3 m with and without the devices are carried out. Horizontal dynamic responses of the structure with and without the devices are compared, and the earthquake isolation and mitigation effect of the devices is evaluated under the horizontal excitations. It can be shown from the experimental and finite element numerical results that the proposed new devices have a good effect on earthquake isolation and mitigation on long-span reticulated structures under horizontal earthquake excitations. [ABSTRACT FROM PUBLISHER]

To reevaluate the association between the costimulatory molecule cytotoxic T lymphocyte-associated antigen4 ( CTLA4) single nucleotide polymorphism (SNP) +49A/G and acute rejection (AR) in renal transplantation, nine studies published before June 2013 were analyzed. Meta-analysis and cumulative meta-analysis (metacum) were performed for each genotype in a random/fixed effect model. The combined odds ratios (OR) with 95% confidence intervals (CI) were calculated to estimate the strength of the association. In the sensitivity analysis, a single study involved in the meta-analysis was deleted each time to investigate the influence of the individual data sets on the pooled ORs. Meta-analysis regression was used for some influence factors, such as year of publication, total number in each group (AR group and control group), ethnicity, the ratio of GG to GA + AA, the ratio of G to A in CTLA4 +49A/G. Overall, a significant correlation was noted between the CTLA4 SNP (+49A/G) and the risk of AR (for GG vs. AG + AA: OR = 1.35, 95% CI = 1.05-1.73, p = 0.02; for G vs. A: OR = 1.21, 95% CI = 1.03-1.42, p = 0.02), especially in the Asian subgroup (for GG vs. AG + AA: OR = 1.79, 95% CI = 1.15-2.78, p = 0.009; for G vs. A: OR = 1.47, 95% CI = 1.04-2.07, p = 0.03). Of the influence factors, the ratio of GG to GA+AA ( p = 0.046) and the ratio of G to A ( p = 0.017) were significant factors. In conclusion, our results suggest that CTLA4 +49A/G contribute to the risk of AR following renal transplantation. [ABSTRACT FROM AUTHOR]

Genetic polymorphisms in cytotoxic T lymphocyte-associated antigen 4 (CTLA4) play an influential role in graft rejection and the long-term clinical outcome of organ transplantation. We investigated the association of five CTLA4 single-nucleotide polymorphisms (SNPs) (rs733618 C/T, rs4553808 A/G, rs5742909 C/T, rs231775 A/G, and rs3087243 G/A) with de novo malignancy in 1463 Chinese renal transplantation (RT) recipients who underwent a 192-month follow-up. Multivariate analyses revealed that recipient rs231775 genotype is significantly associated with tumorigenesis (P=0.012). Multiplicative interaction between rs231775 AA and possible risk factors of malignancy revealed two significant results: rs231775 AA × primary diseases and rs231775 AA × number of HLA-mismatch. The frequency of haplotype TACAG was significantly higher in the tumor group (17.07%) than that in the nontumor group (1.53%). In addition, aristolochic acid nephropathy (P=0.003) and the time of discovery of tumor (P=0.000) also were independently associated with tumorigenesis. Our data show that the CTLA4 genotype rs231775 AA may be one of risk factors for the development of malignancy and haplotype TACAG was susceptible haplotype in Chinese kidney transplant recipients. [ABSTRACT FROM AUTHOR]