Complex causal association between genetically predicted 731 immunocyte phenotype and osteonecrosis: a bidirectional two-sample Mendelian randomization analysis.

PURPOSE: Previous studies have explored the role of immune cells on osteonecrosis. This Mendelian randomization (MR) study further assessed 731 immunocyte phenotypes on osteonecrosis, whether a causal relationship exists, and provides some evidence of causality. METHODS: The 731 immunocyte phenotypes and osteonecrosis data used in this study were obtained from their respective genome-wide association studies (GWAS). The authors used inverse variable weighting (IVW) as the primary analysis method. In addition, the authors simultaneously employed multiple analytical methods, including MR-Egger, weighted mode, simple mode, and weighted median, to strengthen the final results. Finally, sensitivity analyses were conducted to verify the stability and feasibility of the data. RESULTS: The results of the IVW method of MR analysis showed that 8 immunocyte phenotypes were positively associated with osteonecrosis [ P <0.05, odds ratio (OR) > 1]; 18 immunocyte phenotypes were negatively associated with osteonecrosis ( P <0.05, OR<1), none of which were heterogeneous or horizontally pleiotropic ( P > 0.05) or reverse causality. In addition to this, in reverse MR, osteonecrosis was positively associated with 10 additional immunocyte phenotypes ( P <0.05, OR > 1) and negatively associated with 14 immunocyte phenotypes ( P <0.05, OR<1). And none of them had heterogeneity and horizontal pleiotropy ( P > 0.05) or reverse causality. CONCLUSIONS: The authors demonstrated a complex causal relationship between multiple immune phenotypes and osteonecrosis through a comprehensive two-way, two-sample MR analysis, highlighting the complex pattern of interactions between the immune system and osteonecrosis.

A correlative study of iron metabolism based on q-Dixon MRI in benign prostatic hyperplasia and prostate cancer.

Clinical staging, Gleason score, and prostate-specific antigen (PSA) have been accepted as factors for evaluating the prognosis of prostate cancer (PCa). With the in-depth study of iron metabolism and the development of multiparametric magnetic resonance imaging technology, we used q-Dixon magnetic resonance imaging (MRI) to measure the iron content of the PCa patients' lesions, and used enzyme-linked immunosorbent assay (ELISA) to measure the iron metabolism indicators in the patients' serum samples, combined with the patients' postoperative clinical data for analysis. We found that the serum indexes were correlated with the T2 star values, International Society of Urological Pathology (ISUP) grade, and pathological classification in PCa patients (all P < 0.001) but not in benign prostatic hyperplasia (BPH) patients (all P > 0.05). The utilization of q-Dixon-based MRI and serum indexes allows the noninvasive measurement of iron content in prostate lesions and the assessment of differential iron metabolism between PCa and BPH, which may be helpful for evaluating the prognosis of PCa.

Anatomic assessment of femoral tunnel by transtibial drilling technique in double-bundle anterior cruciate ligament reconstruction: an in vivo study.

OBJECTIVE: To evaluate the anatomy of femoral tunnels created by simulated transtibial technique in double-bundle anterior cruciate ligament (ACL) reconstruction. METHODS: Two tibial tunnels, anteromedial (AM) and posterolateral (PL), were drilled 45?and 55?to tibial plateau respectively. On the femoral side, the AM and PL tunnels were drilled through anteriomedial portal. After the four tunnels were established, the shaft of a reamer was introduced into the joint through tibial tunnel and reached against the lateral wall of intercondylar notch. The position that the reamer shaft can reach was marked and recorded. RESULTS: Neither femoral AM nor PL tunnel opening can be fully or partially reached by the reamer shaft through the tibial AM tunnel in all cases. The evaluation through the tibial PL tunnel showed that only in 8 of 50 cases (16%) the femoral AM tunnel opening and in 4 cases (8%) the PL opening can be fully reached. On the other hand, in 12 cases (24%) the femoral AM tunnel opening and in 10 cases (20%) the PL opening can be partially reached by the shafts through the tibial PL tunnel. CONCLUSION: The result strongly suggests that transtibial technique is not well competent for femoral tunnel drilling in anatomic double-bundle ACL reconstruction as we have hypothesized.