Development of in vitro osteoporosis model in minipig proximal humerus and femur: validation in histological and biomechanical study.

BACKGROUND: The minipig has been used for research in various fields of medicine, even in orthopedics. Though previous studies have already suggested other methods to create osteoporotic bone, those methods had some disadvantages for taking time and efforts. Therefore, we aimed to generate osteoporotic proximal humerus and proximal femur of minipig using EDTA solution and validate their properties through dual energy X-ray absorptiometry (DEXA), micro-CT study, histological and biomechanical ways. METHODS: Six minipigs were used. Out of a total of 12 proximal humerus (PH) and 12 proximal femurs (PF), 6 PH and 6 PF were used as the decalcified group and the opposite side as the non-decalcified group. In vitro decalcification with Ca-chelating agents (0.5 M EDTA solution, pH 7.4) was used. Area BMD (aBMD) was measured using DEXA, Volumetric BMD (vBMD), and microstructure were measured using micro-CT. Universal testing machine was used to measure ultimate load to failure (ULTF). Each group was compared using two types of suture anchors (all-suture anchor, ASA, and conventional screw type anchor, CA). RESULTS: There was a significant difference in aBMD and cortical thickness (aBMD: decalcified, 0.433 ± 0.073 g/cm2, undecalcified, 0.962 ± 0.123 g/cm2, p < 0.001; cortical thickness: decalcified, 0.33 ± 0.34 mm, undecalcified, 1.61 ± 0.45 mm, p < 0.001). In the case of ASA, the ULTF was significantly lower in the decalcified group (decalcified: 176.6 ± 74.2 N, non-decalcified: 307.7 ± 116.5 N, p = 0.003). In the case of CA, there was no significant difference (decalcified: 265.1 ± 96.0 N, undecalcified: 289.4 ± 114.5 N, p = 0.578). CONCLUSION: We demonstrated that decalcification with EDTA solution significantly decreased aBMD, vBMD, and cortical thickness. Decalcified minipig bone using EDTA resulted in similar biomechanical properties as osteoporotic human bone with respect to anchor pull-out.

Remplissage in Addition to Arthroscopic Bankart Repair for Shoulder Instability With On-Track Hill-Sachs Lesions Reduces Residual Apprehension Without External Rotation Limitation.

PURPOSE: To evaluate the role of remplissage as an adjunct to Bankart repair in patients with recurrent anterior shoulder dislocation combined with on-track Hill-Sachs lesion. METHODS: Arthroscopic Bankart repair with remplissage data (December 2018-2020) were collected (BR group). Inclusion criteria were (1) recurrent anterior shoulder dislocation, (2) on-track Hill-Sachs lesion, (3) minimal/subcritical glenoid bone loss (<17%), and (4) postoperative follow-up >1 year. Exclusion criteria were (1) revision surgery, (2) first dislocation with acute glenoid rim fracture, and (3) combined with other surgery. The control group was identified in Bankart repair-only cohort (B group). All patients were evaluated preoperatively, and at 3 weeks, 6 weeks, 3 months, 6 months, and then annually postoperatively. Visual analogue scale for pain, Self-Assessment Numerical Evaluation, American Shoulder and Elbow Surgeons Shoulder score, ROWE, and Western Ontario Shoulder Instability were evaluated at preoperative and final follow-up. Residual apprehension experience and external rotation deficit were evaluated. Patients, who were followed-up for more than 1 year, were asked how often they experienced any subjective apprehension in 4 grades (1: always, 2: frequently, 3: occasionally, 4: never). Patients who had a history of recurrent dislocation or revision surgery were investigated. RESULTS: In total, 53 patients (B, 28; BR, 25) were included. At final follow-up, both groups showed improvement in 5 clinical scores postsurgery (P < .001). The BR group showed greater ROWE scores than the B group (B: 75.2 ± 13.6, BR: 84.4 ± 10.8; P = .009). Residual apprehension patient ratio (B: 71.4% [20/28], BR: 32% [8/25]; P = .004) and the mean subjective apprehension grade (B: 3.1 ± 0.6, BR: 3.6 ± 0.6; P = .005) showed statistically significant difference, whereas no patients in either group experienced external rotation deficit (B: 14.8 ± 12.9°, BR: 18.0 ± 15.2°, P = .420). Only 1 patient in the B group had not responded to surgery, with dislocation recurrence (P = .340). CONCLUSIONS: Remplissage with arthroscopic Bankart repair in on-track Hill-Sachs lesion has a role in reducing residual apprehension without external rotation limitation. LEVEL OF EVIDENCE: Level III, retrospective comparative therapeutic trial.

Licochalcone A Exerts Anti-Cancer Activity by Inhibiting STAT3 in SKOV3 Human Ovarian Cancer Cells.

Licochalcone A (LicA), a major active component of licorice, has been reported to exhibit various pharmacological actions. The purpose of this study was to investigate the anticancer activity of LicA and detail its molecular mechanisms against ovarian cancer. SKOV3 human ovarian cancer cells were used in this study. Cell viability was measured using a cell counting kit-8 assay. The percentages of apoptotic cells and cell cycle arrest were determined by flow cytometry and Muse flow cytometry. The expression levels of proteins regulating cell apoptosis, cell cycle, and the signal transducer and activator of transcription 3 (STAT3) signaling pathways were examined using Western blotting analysis. The results indicated that LicA treatment inhibited the cell viability of SKOV3 cells and induced G2/M phase arrest. Furthermore, LicA induced an increase in ROS levels, a reduction in mitochondrial membrane potential, and apoptosis accompanied by an increase in cleaved caspases and cytoplasmic cytochrome c. Additionally, LicA caused a dramatic decrease in STAT3 protein levels, but not mRNA levels, in SKOV3 cells. Treatment with LicA also reduced phosphorylation of the mammalian target of rapamycin and eukaryotic translation initiation factor 4E-binding protein in SKOV3 cells. The anti-cancer effects of LicA on SKOV3 cells might be mediated by reduced STAT3 translation and activation.

Low-Molecular-Weight ß-1,3-1,6-Glucan Derived from Aureobasidium pullulans Exhibits Anticancer Activity by Inducing Apoptosis in Colorectal Cancer Cells.

ß-glucan, a plant polysaccharide, mainly exists in plant cell walls of oats, barley, and wheat. It is attracting attention due to its high potential for use as functional foods and pharmaceuticals. We have previously reported that low-molecular-weight Aureobasidium pullulans-fermented ß-D-glucan (LMW-AP-FBG) could inhibit inflammatory responses by inhibiting mitogen-activated protein kinases and nuclear factor-κB signaling pathways. Bases on previous results, the objective of the present study was to investigate the therapeutic potential of LMW-AP-FBG in BALB/c mice intracutaneously transplanted with CT-26 colon cancer cells onto their backs. Daily intraperitoneal injections of LMW-AP-FBG (5 mg/kg) for two weeks significantly suppressed tumor growth in mice bearing CT-26 tumors by reducing tumor proliferation and inducing apoptosis as compared to phosphate buffer-treated control mice. In addition, LMW-AP-FBG treatment reduced the viability of CT-26 cells in a dose-dependent manner by inducing apoptosis with loss of mitochondrial transmembrane potential and increased activated caspases. Taken together, LMW-AP-FBG exhibits anticancer properties both in vivo and in vitro.

Purple corn extract alleviates 2,4-dinitrochlorobenzene-induced atopic dermatitis-like phenotypes in BALB/c mice.

Zea mays L. (Poaceae), also known as purple corn, is an annual herbaceous plant that is grown as food for human consumption in a variety of forms, including cooking oils and sweeteners in processed food and beverage products. The purpose of this study was to determine whether a novel purple corn extract, FB801, might have an anti-atopic dermatitis (AD) effect on AD-like skin lesions induced by 2,4-dinitrochlorobenzene (DNCB) in BALB/c mice. Topical sensitization (1%) and challenge (0.3%) by DNCB were performed on the dorsal skin and right ear of BALB/c mice to induce AD. Following FB801 and dexamethasone administered orally, the severity of skin lesions was examined macroscopically and histologically. Serum levels of immunoglobulin E (IgE) and various cytokines were determined by enzyme-linked immunosorbent assay. Oral administration of FB801 significantly reduced typical symptoms of AD (erythema/bleeding, swelling, molting/erosion and scaling/drying), scratching frequencies, and the recruitment of inflammatory and mast cells. In addition, FB801 suppressed serum levels of IgE and T helper (Th)2 type cytokines such as interleukin (IL)-4 and IL-10 in DNCB-treated BALB/c mice. Furthermore, FB801 reduced the degradation of inhibitor of nuclear factor-κB proteins (NF-κB) in tumor necrosis factor (TNF)-α-stimulated human keratinocyte (HaCaT) cells. These results suggest that FB801 inhibited the development of the AD-like skin symptoms by regulating Th1 and Th2 responses in the skin lesions in mice and suppressing TNF-α induced NF-κB activation in HaCaT cells, suggesting that FB801 has potential application as an effective alternative therapy for the prevention and management of AD.

Is It Beneficial to Remove the Pedicle Screw Instrument After Successful Posterior Fusion of Thoracolumbar Burst Fractures?

STUDY DESIGN: Case-control study. OBJECTIVE: To investigate the clinical and radiological outcomes of pedicle screw removal after successful fusion of thoracolumbar burst fractures. SUMMARY OF BACKGROUND DATA: Implant removal is a common procedure in orthopedic surgery, although the benefits of and indications for removal remain controversial. Previous studies on pedicle screw removal have reported conflicting outcomes, because the study subjects and surgical goals were heterogeneous in nature. METHODS: We studied 45 consecutive patients who underwent implant removal and a control cohort of 45 age- and sex-matched patients who retained their spinal implants after successful posterior fusion of thoracolumbar burst fractures using pedicle screw instrument. In most cases, long-segment instrumentation with short-segment posterior fusion was performed. The mean elapsed period prior to implant removal after index fracture surgery was 18.3 ± 17.6 months. A visual analogue scale for back pain was applied, the Oswestry disability index calculated, and radiological parameters derived at the time of implant removal and 1 and 2 years postoperatively obtained. These data were compared with those of the control group evaluated at the same times after index fracture surgery. RESULTS: Patient demographics, mechanisms of injury, fracture morphologies, and the outcomes of index fracture surgery were similar between the 2 groups. The mean visual analogue scale and Oswestry disability index scores were better at both the 1- and 2-year follow-ups in the implant removal group than in the control group (all P values = 0.000). The segmental motion angle of the implant removal group was 1.6° ± 1.5° at the time of implant removal, and increased significantly to 5.8° ± 3.9° at 1-year follow-up (P = 0.000), and was maintained at this level at the 2-year follow-up (5.9° ± 4.1°) (P = 0.000). CONCLUSION: In patients treated successfully for thoracolumbar burst fractures, pedicle screw removal is beneficial because it alleviates pain and disability. Restoration of the segmental motion angle after implant removal may contribute to the clinical improvement. LEVEL OF EVIDENCE: 3.