Biomechanical study of posterior cruciate ligament tibial arrest avulsion fracture fixation with triple tibial channel net sutures.

To investigate the biomechanical properties of posterior cruciate ligament avulsion fractures of the tibia fixed using four different methods, including triple tibial channel net suture fixation. In 40 porcine knees, a standardized bony avulsion of the posterior cruciate ligament was generated. Double tibial bone channel suture fixation was performed in group A, double-head hollow compression screw fixation was performed in group B, triple tibial bone channel net suture fixation was performed in group C, and cortical suspension EndoButton fixation was performed in group D. The constructs were cyclically loaded 500 times (10 to 100 N) to measure the initial displacement and stiffness values. Subsequently, loading to failure was performed, and the yield load and peak load were measured. The results were analysed by one-way ANOVA, with significance set at P < 0.05. The initial displacement in group D (1.00 ± 0.20 mm) was lower than that in group C (1.46 ± 0.33 mm, P = 0.000), group B (1.91 ± 1.71 mm, P = 0.000) and group A (3.91 ± 0.79 mm, P = 0.000), but there was no significant difference between groups B and C (P = 0.055). The initial stiffness in group A (50.59 ± 6.89 N/mm) was lower than that in group C (67.21 ± 12.80 N/mm, P = 0.001), group D (71.18 ± 9.20 N/mm, P = 0.000) and group B (78.67 ± 5.91 N/mm, P = 0.000). However, there was no significant difference between groups B and D or between groups C and D (P = 0.111 and P = 0.391). The yield load in group A (554.86 ± 71.43 N) was lower than that in group C (767.00 ± 34.53 N, P = 0.000), group D (777.62 ± 73.03 N, P = 0.000) and group B (837.50 ± 55.73 N, P = 0.000). There was no significant difference between groups C and D (P = 0.729). The peak load in group A (667.38 ± 61.54 N) was lower than that in group C (842.00 ± 26.20 N, P = 0.000), group D (867.63 ± 63.42 N, P = 0.000) and group B (901.25 ± 54.38 N, P = 0.000). There was no significant difference between groups C and D (P = 0.346). Different failure modes were found among the four groups. The triple tibial bone channel suture fixation group showed better initial stability and fixation strength, which was comparable to that in the cortical suspension EndoButton fixation group and double-head hollow compression screw fixation group and significantly stronger than that in the double tibial bone channel suture fixation group. This study analysed the dynamic and static indexes of posterior cruciate ligament tibial avulsion fractures fixed by four different fixation methods under cyclic loading tests and single failure loading tests, providing a theoretical basis for clinical treatment.

Outcomes of physeal-sparing posterior cruciate ligament reconstruction for adolescents with an open physis.

PURPOSE: The posterior cruciate ligament (PCL) rupture rarely occurs, especially in skeletally immature adolescents, and poses a dilemma in appropriately managing the open physis with its vast growth potential. However, although many epiphyseal-protecting techniques for anterior cruciate ligament (ACL) reconstruction have been reported, a similar problem in PCL reconstruction has received scant attention and needs more relevant research. So, this study aims to evaluate the short-term clinical and imaging results of the arthroscopic physeal-sparing reconstruction program. METHOD: All the 13 patients we reviewed in this study have accepted the arthroscopic physeal-sparing PCL reconstruction from January 2019 to December 2022 in our Department of Orthopedics. Primary demographic data collected include gender (8 males and 5 females), age (11-15 years, average 13.3 years), follow-up period (15-35 months, average 25.2 months), injury mechanism (nine non-contact injuries and four contact injuries), and days following injury (1-10 days, average 5.3 days). The assessment of clinical outcomes included pre- and postoperative physical examination, knee functional scores, and imaging data. RESULT: All patients in this study were followed up with an average 25.2-month (range 15-35 months) follow-up period. All the cases preoperatively had a positive posterior drawer test and turned negative at the final follow-up. The average ROM improved from 103.6° ± 11.4° to 132.6° ± 3.6° at the last follow-up (p < 0.05). The VAS score decreased from 5.8 ± 1.6 to 0.9 ± 0.5 (p < 0.05); the average KT-1000 healthy-side to affected-side difference decreased from 11.3 ± 1.6 to1.8 ± 0.5 mm. The comparison of all the knee functional scores (IKDC, Tegner scores, and Lysholm) at preoperative and last follow-up showed a significant difference (p < 0.05). None of the cases had operation-related complications, and all recovered to sports well. CONCLUSION: The arthroscopic physeal-sparing posterior cruciate ligament reconstruction is a dependable and recommended treatment for posterior cruciate ligament rupture in adolescents with open physis, showing a striking improvement in knee function without growth arrest and angular deformity of the affected limb in the short-term follow-up.

Association between sarcopenia-related traits and cardiovascular diseases: a bi-directional Mendelian randomization study.

Background: The two geriatric diseases, sarcopenia and cardiovascular disease (CVD), often coexist, yet the causal relationship is unclear. However, few studies focus on the effect of muscle mass on CVD. This comprehensive study is dedicated to unearthing the potential connection between sarcopenia-related traits and CVD at the genetic level. Method: A two-sample bi-directional Mendelian randomization (MR) study was conducted. In the first stage, we performed MR analysis regarding coronary heart disease (CHD), stroke, and myocardial infarction (MI) as exposure factors to reveal their effect on appendicular lean mass (ALM) and hand grip strength. In the second stage, we reverse the position of exposures and outcomes. The inverse variance weighted (IVW) method was used as the primary approach to reveal the potential causation between the exposure and outcome. Results: The results of the IVW method revealed a negative causal effect of ALM on CHD (OR = 0.848, 95% CI = 0.804 to 0.894, p = 8.200E-10), stroke (OR = 0.931, 95% CI = 0.890 to 0.975, p = 2.220E-03), and MI (OR = 0.810, 95% CI = 0.694 to 0.901, p = 1.266E-13). Additionally, the left-hand grip strength is a significant protective factor for CHD (OR = 0.737, 95% CI = 0.601 to 0.904, p = 3.353E-03) and MI (OR = 0.631, 95% CI = 0.515 to 0.765, p = 2.575E-06), but is not causally linked to the stroke (OR = 0.971, 95% CI =0.829 to 1.139, p = 0.720). Meanwhile, the same conclusion about the effect of right-hand grip strength on CHD (OR = 0.681, 95% CI = 0.558 to 0.832, p = 1.702E-05), MI (OR = 0.634, 95% CI = 0.518 to 0.776, p = 9.069E-06), and stroke (OR = 1.041, 95% CI = 0.896 to 1.209, p = 0.604) was obtained. However, no significant causal effect of CVD (CHD, stroke, MI) on sarcopenia-related traits (ALM, handgrip strength) was found. Conclusion: There is a unidirectional causal relationship between sarcopenia and CVD. The loss of muscle mass and strength has a significant causal role in promoting the occurrence and development of CVD, providing a reference for the prevention and treatment of comorbidities in older people.

Geriatric syndromes, chronic inflammation, and advances in the management of frailty: A review with new insights.

As people age, geriatric syndromes characterized by frailty significantly impact both clinical practice and public health. Aging weakens people's immune functions, leading to chronic low-grade inflammation that ultimately contributes to the development of frailty. Effectively managing geriatric syndromes and frailty can help alleviate the economic burden of an aging population. This review delves into the intricate relationship among aging, infection-induced inflammation, chronic inflammation, and frailty. In addition, it analyzes various approaches and interventions to address frailty, such as smart rehabilitation programs and stem-cell treatments, offering promising solutions in this new era. Given the importance of this topic, further research into the mechanisms of frailty is crucial. Equally essential is the devising of relevant measures to delay its onset and the formulation of comprehensive clinical, research, and public health strategies to enhance the quality of life for elderly individuals.

A comprehensive review of natural products with anti-hypoxic activity.

Natural products exhibit substantial impacts in the field of anti-hypoxic traetment. Hypoxia can cause altitude sickness and other negative effect on the body. Headache, coma, exhaustion, vomiting and, in severe cases, death are some of the clinical signs. Currently, hypoxia is no longer just a concern in plateau regions; it is also one of the issues that can not be ignored by urban residents. This review covered polysaccharides, alkaloids, saponins, flavonoids, peptides and traditional Chinese compound prescriptions as natural products to protect against hypoxia. The active ingredients, effectiveness and mechanisms were discussed. The related anti-hypoxic mechanisms involve increasing the hemoglobin (HB) content, glycogen content and adenosine triphosphate (ATP) content, removing excessive reactive oxygen species (ROS), reducing lipid peroxidation, regulating the levels of related enzymes in cells, protecting the structural and functional integrity of the mitochondria and regulating the expression of apoptosis-related genes. These comprehensive summaries are beneficial to anti-hypoxic research and provide useful information for the development of anti-hypoxic products.

Tyrosinase Inhibitory Peptides from Enzyme Hydrolyzed Royal Jelly: Production, Separation, Identification and Docking Analysis.

Tyrosinase is inextricably related to the development of Alzheimer's disease. The effects of natural tyrosinase inhibitors on human health have attracted widespread attention. This study aimed to isolate and analyze the tyrosinase (TYR) inhibitory peptides in the enzymatic digestion products of royal jelly. We first analyzed optimal process conditions for the enzymatic digestion of royal jelly by single-factor and orthogonal experiments and then used gel filtration chromatography to obtain five fractions (D1~D5) with molecular weights ranging from 600 to 1100 Da. LC-MS/MS was applied to identify the fractions with the highest activity, and the obtained peptides were screened and molecularly docked using AutoDock Vina. The results showed that the optimal enzymatic conditions for tyrosinase inhibition rate were acid protease, enzyme addition 10,000 U/g, initial pH 4, feed-to-liquid ratio 1:4, enzymatic temperature 55 °C, and enzymatic time 4 h. The D4 fraction had the most significant TYR inhibitory activity. The IC50 values of the three new peptides with the strongest TYR inhibitory activity, TIPPPT, IIPFIF, and ILFTLL, were obtained as 7.59 mg/mL, 6.16 mg/mL, and 9.25 mg/mL, respectively. The molecular docking results showed that aromatic and hydrophobic amino acids were more favorable to occupy the catalytic center of TYR. In conclusion, the new peptide extracted from royal jelly has the potential to be used as a natural TYR inhibitory peptide in food products with health-promoting properties.

Macitentan treatment of portopulmonary hypertension with hepatopulmonary syndrome: a case report and literature review.

Pulmonary arterial hypertension-targeted therapies in portopulmonary hypertension (PoPH) are scarce, let alone for patients with chronic liver failure (CLF) and hepatopulmonary syndrome (HPS). A 48-year male was admitted to the hospital because of cirrhosis for 18 years, systemic oedema, and chest distress after exercise for 1 week. He was diagnosed with CLF, PoPH, and HPS. After 7 weeks of macitentan treatment, the patient's activity tolerance, pulmonary artery systolic pressure, arterial partial pressure of oxygen (PaO2 ), cTNI, and NT-proBNP changes indicated gradual recovery, without hepatic safety concerns. This case indicated that administering macitentan in patients diagnosed as PoPH (with CLF and HPS) may be efficient and safe enough in a clinical setting.

Design and performance analysis of 3D-printed stiffness gradient femoral scaffold.

Studies on 3D-printed porous bone scaffolds mostly focus on materials or structural parameters, while the repair of large femoral defects needs to select appropriate structural parameters according to the needs of different parts. In this paper, a kind of stiffness gradient scaffold design idea is proposed. Different structures are selected according to the different functions of different parts of the scaffold. At the same time, an integrated fixation device is designed to fix the scaffold. Finite element method was used to analyze the stress and strain of homogeneous scaffolds and the stiffness gradient scaffolds, and the relative displacement and stress between stiffness gradient scaffolds and bone in the case of integrated fixation and steel plate fixation. The results showed that the stress distribution of the stiffness gradient scaffolds was more uniform, and the strain of host bone tissue was changed greatly, which was beneficial to the growth of bone tissue. The integrated fixation method is more stable, less stress and evenly distributed. Therefore, the integrated fixation device combined with the design of stiffness gradient can repair the large femoral bone defect well.

The association between callous-unemotional traits and suicide ideation among youth: A conditional process analysis.

BACKGROUND: The relationship between callous-unemotional (CU) traits (the affective facet of psychopathy and the psychopathy that occurs during childhood and adolescence) and suicide ideation (SI) remains unclear. The mechanisms underlying this association still have a gap in the literature. The aims of this study were to determine whether and how callous-unemotional traits were associated with suicide ideation, and to evaluate the mediating effect of negative affect (includes irritability, depression, and anxiety) and the moderating effect of future orientation on the association. METHODS: Data were extracted from a longitudinal study involving middle and high school students, with 1,913 students (55.3% girls) aged 11 to 19 years (14.9 ± 1.6 years) completing a self-reported online survey. The conditional process analysis was examined using Mplus 8.3. RESULTS: We found that callous-unemotional traits positively predicted youths' current suicide ideation, with the observed positive relationship partly mediated by negative affect. However, callous-unemotional traits did not predict the worst-point suicide ideation, which indicated the connection fully mediated by negative affect. Furthermore, future orientation moderated these indirect effects. LIMITATIONS: Use of self-report measures and cross-sectional design. CONCLUSIONS: These findings provided evidence for current debates and conflicting conclusions, and set the foundation for future research, as well as implied the important intervention goals for reducing suicide ideation in youth.

Decreased medial posterior tibial slope is associated with an increased risk of posterior cruciate ligament rupture.

PURPOSE: It remains unclear whether there is an association between posterior cruciate ligament (PCL) rupture and the medial posterior tibial slope (MTS) or lateral posterior tibial slope (LTS). The present case-control study aimed to investigate a possible association between primary PCL rupture and MTS or LTS measured by magnetic resonance imaging (MRI). METHODS: A retrospective case-control study was conducted. Patients with primary PCL ruptures but not with anterior cruciate ligament injuries, were 1:1 matched by age and sex to a control group with no evidence of knee ligament injuries. Knee MRI was used to measure the MTS and LTS. In addition, the receiver operating characteristic (ROC) analysis was performed to identify an optimal cut-off value of the MTS and/or LTS. RESULTS: In total, 46 patients with PCL ruptures (32 males, 14 females) and 46 controls (32 males, 14 females) were included in this study. The MTS was significantly lower in the patients with PCL ruptures (3.0° ± 2.2°) than in the control group (5.1° ± 2.3°, p < 0.001). The mean LTS/MTS ratio was significantly higher in patients with PCL ruptures (2.6 ± 2.5) than in the control group (1.3 ± 1.3, p = 0.001). However, the LTS was not significantly different between patients with PCL ruptures and the controls (4.4° ± 2.3° vs. 5.3° ± 2.6°, n.s.). After the MTS was determined to be a significant predictor, the ROC analysis was performed. The ROC analysis revealed the most accurate MTS cut-off of < 3.9°, with a sensitivity of 76.1% and a specificity of 73.9%. CONCLUSION: A decreased MTS and an increased LTS/MTS ratio are associated with an increased risk of primary PCL rupture. People with MTS < 3.9° are particularly at risk for PCL ruptures, and prevention and intervention programs for PCL ruptures should be developed and targeted towards them. LEVELS OF EVIDENCE: Level III.

Semi-Supervised Instance-Segmentation Model for Feature Transfer Based on Category Attention.

In the task of image instance segmentation, semi-supervised instance segmentation algorithms have received constant research attention over recent years. Among these algorithms, algorithms based on transfer learning are better than algorithms based on pseudo-label generation in terms of segmentation performance, but they can not make full use of the relevant characteristics of source tasks. To improve the accuracy of these algorithms, this work proposes a semi-supervised instance segmentation model AFT-Mask (attention-based feature transfer Mask R-CNN) based on category attention. The AFT-Mask model takes the result of object-classification prediction as "attention" to improve the performance of the feature-transfer module. In detail, we designed a migration-optimization module for connecting feature migration and classification prediction to enhance segmentation-prediction accuracy. To verify the validity of the AFT-Mask model, experiments were conducted on two types of datasets. Experimental results show that the AFT-Mask model can achieve effective knowledge transfer and improve the performance of the benchmark model on semi-supervised instance segmentation.

Femtosecond laser treatment promotes the surface bioactivity and bone ingrowth of Ti6Al4V bone scaffolds.

In this study, a femtosecond laser with a wavelength of 800 nm was used to modify the surface of a titanium alloy bone scaffold created via selective laser melting (SLM). The outcomes demonstrated that the surface morphology of the bone scaffold after femtosecond laser treatment was micro-nano morphology. The hydrophobic structure of the scaffold was changed into a super-hydrophilic structure, improving the surface roughness, which was highly helpful for osteoblast adhesion and differentiation. The femtosecond laser surface treatment in vitro samples produced a thick layer of hydroxyapatite (HAP) with improved surface bioactivity. The effectiveness of osseointegration and interstitial growth of the specimens treated with the femtosecond laser surface were found to be better when bone scaffolds were implanted into the epiphysis of the tibia of rabbits. As a result, femtosecond laser therapy dramatically enhanced the surface activity of bone scaffolds and their capacity to integrate with the surrounding bone tissues, serving as a trustworthy benchmark for future biological scaffold research.

Single-stage arthroscopic-assisted treatment of anteromedial tibial plateau fracture with posterolateral corner injury: a retrospective study.

BACKGROUND: Anteromedial tibial plateau fracture with posterolateral corner (PLC) injury is a relatively rare combined injury in the clinic. In addition, there is no unified treatment scheme for this combined injury. The purpose of this study was to evaluate the clinical and imaging results of single-stage arthroscopic-assisted surgery for anteromedial tibial plateau fracture with PLC injury, and to explore the advantages of this surgical technique. METHOD: In this retrospective study, a total of 9 patients (7 males and 2 females) were included, aged 24-64 years (average 40.7 years), treated in our Department of Orthopedics from January 2016 to January 2021. In the preoperative evaluations, there were 9 cases of anteromedial tibial plateau fractures with PLC injuries, 6 cases of concomitant PCL injuries, 6 cases of concomitant medial or lateral meniscus injuries, and 2 cases of concomitant fibular head avulsion fractures. All patients underwent single-stage arthroscopic-assisted surgery. RESULTS: All patients were followed up, and the average follow-up period was 15.2 months (range 12-18 months). The average operation time was 135.6 min (range 100-160 min), and the average surgical blood loss was 87.2 ml (range 60-110 ml). The anatomical reduction was achieved in 9 cases, and the anatomical reduction rate was 100%. The average fracture healing time was 13.1 weeks (range 12-16 weeks). At the last follow-up, the average VAS score was 1 (range 0-2); the average Lysholm function score was 90.7 (range 86-95), and the average IKDC score was 91.4 (range 88-95); the average knee extension angle of all patients was 0° and the average knee flexion angle was 128.3° (average 120-135°); The posterior drawer test, the Lachman test and the dial test were negative for all cases. None of the patients had operation-related complications. CONCLUSION: Single-stage arthroscopy-assisted surgery in the treatment of anteromedial tibial plateau fracture with PLC injury can achieve good clinical outcomes, restore the stability of the knee joint, and reduce the risk of severe lower extremity dysfunction.