Biologic Therapies in Stress Fractures: Current Concepts

Stress fractures, a common overuse injury in physically active individuals, present a significant challenge for athletes and military personnel. Patients who sustain stress fractures have demanding training regimes, where periods of rest and immobilisation have unacceptable negative consequences on sport goals and finances. Aside from being an overuse injury, there are various contributing risk factors that put certain individuals at risk of a stress fracture. The main two being nutritional deficiencies and hormonal variations which have significant effects on bone metabolism and turnover. Historically, treatment of stress fractures focused on conservative strategies such as rest and immobilisation. Calcium and vitamin D deficiencies have been closely linked to stress fractures and so over time supplementation has also played a role in treatment. With the introduction of biologics into orthopaedics, newer treatment strategies have been applied accelerate fracture healing and perhaps improve fracture callus quality. If such therapies can reduce, time spent away from sport and activity, it would be ideal for treating stress fractures. This article aims to offers insights into the evolving landscape of stress fracture management. It investigates the pre-clinical evidence and available published clinical applications. Though fracture healing is well understood, the role of biologics for fracture healing is still indeterminate. Available literature for the use of biologics therapies in stress fractures is restricted and most reports have used biologics as a supplement to surgical fixation in subjects in studies that lack control groups. Randomised control trials have been proposed and registered by a few groups with results awaited. Assessing individuals for risk factors, addressing hormonal imbalances and nutritional deficiencies seem an effective approach to addressing the burden of stress fractures. We await better designed trials and studies to accurately determine the clinical benefit of adding biologics to management of these injuries.

Improved Measurements of Muonic Helium Ground-State Hyperfine Structure at a Near-Zero Magnetic Field

Muonic helium atom hyperfine structure (HFS) measurements are a sensitive tool to test the three-body atomic system and bound-state quantum electrodynamics theory, and determine fundamental constants of the negative muon magnetic moment and mass. The world's most intense pulsed negative muon beam at the Muon Science Facility of the Japan Proton Accelerator Research Complex allows improvement of previous measurements and testing further CPT invariance by comparing the magnetic moments and masses of positive and negative muons (second-generation leptons). We report new ground-state HFS measurements of muonic helium-4 atoms at a near-zero magnetic field, performed for the first time using a small admixture of CH_{4} as an electron donor to form neutral muonic helium atoms efficiently. Our analysis gives Δν=4464.980(20)  MHz (4.5 ppm), which is more precise than both previous measurements at weak and high fields. The muonium ground-state HFS was also measured under the same conditions to investigate the isotopic effect on the frequency shift due to the gas density dependence in He with CH_{4} admixture and compared with previous studies. Muonium and muonic helium can be regarded as light and heavy hydrogen isotopes with an isotopic mass ratio of 36. No isotopic effect was observed within the current experimental precision.

Freeze-dried noncoagulating platelet-derived factor concentrate is a safe and effective treatment for early knee osteoarthritis

PURPOSE

While a wide variety of platelet-rich plasma (PRP) solutions has been developed, innovation continues. In this case, the freeze-dried platelet factor concentrate (PFC-FD) represents another step in PRP refinement. The preparation of PFC-FD at a central laboratory with freeze drying for shelf stabilization should provide additional quality improvements if clinical effectiveness can be demonstrated. Therefore, this study was undertaken to assess the safety and effectiveness of PFC-FD in a prospective open-label trial of patients suffering from knee osteoarthritis (OA).

METHODS

312 consecutive knee OA patients (67% female, mean age 63 ± 10 years), were prospectively recruited in an outpatient knee clinic in Japan. Of these, 10 (3.2%) were lost to follow-up at < 12 months and 17 (5.5%) sought additional knee therapy during the follow-up period. The primary outcome of interest was achievement of the OMERACT-OARSI responder criteria with secondary outcomes of adverse events and PROMs scores 1, 3, 6, 12 months following a single PFC-FD injection.

RESULTS

285 patients (91%) completed 12 month PROMs. The 17 who sought additional therapy were considered failures leaving an effective sample size of 302 for our primary outcome in which 62% of patients achieved OMERACT-OARSI responder status by 12 months. This varied by OA class with Kellgren-Lawrence grade 4 patients 3.6 times less likely to be responders than grade 1-2 patients. 6% of patients experienced a non-serious adverse event, primarily pain or swelling at the injection site.

CONCLUSIONS

PFC-FD provides an observable clinical improvement in 62% of knee OA patients at 12 months post-injection with very little risk of any clinically relevant adverse event. Of course, nearly 40% of patients did not experience an observable clinical improvement, primarily among those with worse KL grades.

LEVEL OF EVIDENCE

Therapeutic, Level II.

Repair of osteochondral defects: efficacy of a tissue-engineered hybrid implant containing both human MSC and human iPSC-cartilaginous particles

Both mesenchymal stromal cells (MSC) and induced pluripotent stem cells (iPSC) offer the potential for repair of damaged connective tissues. The use of hybrid implants containing both human MSC and iPSC was investigated to assess their combined potential to yield enhanced repair of osteochondral defects. Human iPSC-CP wrapped with tissue engineered constructs (TEC) containing human MSC attained secure defect filling with good integration to adjacent tissue in a rat osteochondral injury model. The presence of living MSC in the hybrid implants was required for effective biphasic osteochondral repair. Thus, the TEC component of such hybrid implants serves several critical functions including, adhesion to the defect site via the matrix and facilitation of the repair via live MSC, as well as enhanced angiogenesis and neovascularization. Based on these encouraging studies, such hybrid implants may offer an effective future intervention for repair of complex osteochondral defects.

Five-Year Outcomes After Implantation of a Scaffold-Free Tissue-Engineered Construct Generated From Autologous Synovial Mesenchymal Stromal Cells for Repair of Knee Chondral Lesions

Background

In an earlier study, a scaffold-free tissue-engineered construct (TEC) derived from autologous synovial membrane mesenchymal stromal cells (MSCs) was developed and demonstrated to be safe and effective for cartilage repair at 2 years postoperatively.

Purpose

To investigate clinical outcomes and magnetic resonance imaging (MRI) findings at 5 years after implantation.

Study Design

Case series; Level of evidence, 4.

Methods

This was an observational first-in-human study limited to 5 patients (age, 28-46 years) with symptomatic knee chondral lesions (size, 1.5-3.0 cm2) on the medial femoral condyle, lateral femoral condyle, or femoral groove. Synovial MSCs were isolated from arthroscopic biopsy specimens and cultured to develop a TEC that matched the lesion size. The TECs were then implanted into chondral defects without fixation and assessed at up to 5 years postoperatively. The patients were clinically evaluated using the visual analog scale for pain, Lysholm score, Tegner score, and Knee injury and Osteoarthritis Outcome Score. An MRI scan evaluation was also performed for morphologic and compositional quality of the repair tissue at both 2 and 5 years of follow-up.

Results

All clinical scores were significantly improved from the preoperative evaluation to the 2- and 5-year follow-ups and the results were stable over time. The MRI scan evaluation showed cartilage defects filled with newly generated tissues with good tissue integration to adjacent host cartilage over time. The cartilage thickness and surface smoothness of the repair cartilage were maintained up to 5 years postoperatively. The MOCART (magnetic resonance observation of cartilage repair tissue) 2.0 Knee Scores remained high at 5 years, although the total points decreased slightly.

Conclusion

The results highlight the efficacy and feasibility of autologous scaffold-free TEC derived from synovial MSCs for regenerative cartilage repair via a sutureless and simple implantation procedure, showing good clinical outcomes and MRI findings with stable results at midterm follow-up. Further follow-up will be needed to assess the long-term quality of the repair tissue.

Small extracellular vesicles derived from human adipose-derived mesenchymal stromal cells cultured in a new chemically-defined contaminate-free media exhibit enhanced biological and therapeutic effects on human chondrocytes in vitro and in a mouse osteoarthritis model

Human small extracellular vesicles (sEVs) derived from adipose-derived mesenchymal stromal cells (ASC) have been reported to suppress the progression of osteoarthritis (OA) in animal studies and subsequently, translation of this potential to assess their clinical efficacy is anticipated. However, fabrication protocols for sEVs to eliminate potential contamination by culture medium-derived components need to be established prior to their clinical use. The purpose of the present studies was to elucidate the influence of medium-derived contaminants on the biological effects of sEVs, and to establish isolation methods for sEVs using a new clinical grade chemically-defined media (CDM). The quantity and purity of ASC-derived sEVs cultured in four different CDMs (CDM1, 2, 3 and 4) were evaluated. The concentrates of the four media incubated without cells were used as the background (BG) control for each set of sEVs. The biological effect of sEVs fabricated in the four different CDMs on normal human articular chondrocytes (hACs) were evaluated in vitro using a variety of methodological assessments. Finally, the sEVs with the highest purity were tested for their ability to suppress the progression of knee OA mouse model. Analysis of the BG controls revealed that CDM1-3 contained detectable particles, while there was no visible contamination of culture media-derived components detected with CDM4. Accordingly, the sEVs fabricated with CDM4 (CDM4-sEVs) exhibited the highest purity and yield. Notably, the CDM4-sEVs were the most efficient in promoting the cellular proliferation, migration, chondrogenic differentiation, and anti-apoptotic activity of hACs. Furthermore, CDM4-sEVs significantly suppressed the osteochondral degeneration in vivo model. Small EVs derived from ASCs cultured in a CDM without detectable contaminants demonstrated enhanced biological effects on hACs and the progression of OA. Thus, sEVs isolated with CDM4 most optimally meet the requirements of efficacy and safety for assessment in their future clinical applications.

Proof-of-Principle Experiment for Testing Strong-Field Quantum Electrodynamics with Exotic Atoms: High Precision X-Ray Spectroscopy of Muonic Neon

To test bound-state quantum electrodynamics (BSQED) in the strong-field regime, we have performed high precision x-ray spectroscopy of the 5g-4f and 5f- 4d transitions (BSQED contribution of 2.4 and 5.2 eV, respectively) of muonic neon atoms in the low-pressure gas phase without bound electrons. Muonic atoms have been recently proposed as an alternative to few-electron high-Z ions for BSQED tests by focusing on circular Rydberg states where nuclear contributions are negligibly small. We determined the 5g_{9/2}- 4f_{7/2} transition energy to be 6297.08±0.04(stat)±0.13(syst)  eV using superconducting transition-edge sensor microcalorimeters (5.2-5.5 eV FWHM resolution), which agrees well with the most advanced BSQED theoretical prediction of 6297.26 eV.

Clinical Safety and Effectiveness of Adipose-Derived Stromal Cell vs Stromal Vascular Fraction Injection for Treatment of Knee Osteoarthritis: 2-Year Results of Parallel Single-Arm Trials

BACKGROUND

There are currently no disease-modifying treatments available for knee osteoarthritis (OA), although cultured adipose-derived stromal cells (ASCs) have shown promise in experimental models. However, given the regulatory limits on the use of cultured cells in humans, previous trials have focused primarily on the stromal vascular fraction (SVF) intra-articular injection. Therefore, the therapeutic value of ASCs for knee OA remains unknown.

PURPOSE

To study ASC versus SVF intra-articular injection in patients with Kellgren-Lawrence (KL) knee OA grades 2 to 4 in parallel single-arm trials.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A total of 80 patients were enrolled, with 42 (72 knees) receiving ASC intra-articular injection and 38 (69 knees) receiving SVF. Patient-reported outcome measures were assessed at 1, 3, 6, 12, and 24 months using the Knee injury and Osteoarthritis Outcome Score 5 (KOOS5) and pain visual analog scale (VAS). The percentages of patients achieving the minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) were also calculated. Per protocol, a subset of the ASC group received an ASC booster injection after 6 months. A repeated-measures analysis of variance compared results between treatment arms and by KL grade over time.

RESULTS

Patient-reported outcome measures improved substantially after both treatments (P < .05 at all time points), with the ASC group more likely to achieve the MCID (50% vs 24%; P = .01) and PASS (45% vs 24%; P = .04) for the pain VAS and the MCID (43% vs 16%; P = .02) for the KOOS5 at 12 months, although not at 24 months. Knees treated with ASC for KL grade 2/3 OA had significantly superior outcomes compared with those with KL grade 4 OA for the KOOS5 (P = .01) and pain VAS (P = .03), but no such difference was observed in knees treated with SVF. Three patients receiving ASCs (7%; all KL grade 3) sought additional nonoperative treatment by 24 months versus 9 patients receiving SVF (24%; all KL grade 3) (P = .06). ASC booster injections conferred no additional benefit. Notably, patients in the ASC cohort reported more injection-site pain and swelling after the booster injection than after the initial injection (P < .01).

CONCLUSION

This represents the first head-to-head comparison of ASCs and SVF for the treatment of knee OA in humans. ASC and SVF injections both substantially improved knee pain and function at all follow-up time points, although ASC injections demonstrated significantly better improvements with regard to the MCID and PASS for the pain VAS and the MCID for the KOOS5 at 12 months. There appears to be no benefit to a booster ASC injection after initial treatment. Given less donor-site morbidity and equivalent superior outcomes at 2 years, the use of ASCs over SVF in the treatment of knee OA may be warranted.

[Efficacy of a Dexamethasone Dose Escalation Regimen with a Cumulative Dose for Preventing Oxaliplatin Hypersensitivity Reactions]

Oxaliplatin is a platinum complex antineoplastic agent widely used for chemotherapy of colorectal cancer. However, one of its side effects is hypersensitivity reactions, the incidence of which increases with a cumulative dose, thereby posing a difficulty to continue oxaliplatin use. Our hospital changed the premedication of oxaliplatin in August 2009 and September 2012. We retrospectively investigated the usefulness of these premedication changes. The results showed no significant difference in the incidence of hypersensitivity between the control group(12.1%)and the group receiving H1 and H2-blockers (12.3%); however, the incidence of hypersensitivity was significantly reduced in the group receiving increased dexamethasone based on the number of courses(2.7%). Therefore, our regimen was found to be effective in preventing hypersensitivity reactions to oxaliplatin.

Two Uncommon Complications Related to Suture Knots After Meniscal All-Inside Suture Repair: A Case Report

CASE

A 17-year-old male patient suffered a radial lateral meniscus tear and underwent an arthroscopic all-inside suture repair. After 7 months, the patient experienced catching. Magnetic resonance imaging and computed tomography revealed an intra-articular loose body without calcification, which was removed surgically. The excised specimen was histopathologically confirmed to be a necrotic meniscus fragment with a suture knot. In addition, cartilage damage because of suspected impingement by a residual suture knot was observed. After removing the loose body and knot, the patient's symptoms were relieved, and he returned to sports.

CONCLUSION

Suture knot-related complications should be considered while performing meniscal repairs.

Posterior Ankle Impingement Caused by Hyaline-Like Cartilage Generation in Ballet Dancers-A Report of 2 Cases

Posterior ankle impingement syndrome is mainly seen in ballet dancers and frequently associated with specific movements in ballet such as pointe and demi pointe in which the whole-body weight is applied to the maximally plantar flexed ankle. We performed arthroscopic debridement for 2 dedicated ballet dancers on the intervening soft tissue causing posterior ankle impingement syndrome (PAIS). In both cases, T2-weighted magnetic resonance imaging (MRI) revealed low-signal intensity of meniscus-like soft tissue without abnormal osseous findings, connecting from the posterior side of the talus to Kager's fat pad. To examine the intervening soft tissue in detail, we performed histological evaluation by hematoxylin and eosin staining, Safranin O fast green staining, and immunohistochemistry for type I collagen and type II collagen. Hematoxylin and eosin staining showed that there was cartilage-like tissue including chondrocyte-like cells in contact with fibrous tissue. The extracellular matrix in the cartilage zone was consistently stained by Safranin O staining and type II collagen without any staining with type I collagen. These findings suggested that the meniscus-like soft tissue appearing as low-signal intensity on MRI at the posterior side of talus included hyaline-like cartilage. To the extent of our knowledge, these were rare cases of hyaline-like cartilage generation causing PAIS in ballet dancers, which might be associated with ballet specific movements resulting in chondrogenesis.

Effect of proton pump inhibitors on the development of hypomagnesemia induced by panitumumab

Panitumumab, a therapeutic agent for unresectable advanced/recurrent colorectal cancer, is a human IgG2 monoclonal antibody that binds to and inhibits the activity of the epidermal growth factor receptor (EGFR). The onset of hypomagnesemia is a known side effect of anti-EGFR inhibitors, including panitumumab, and it is thought that inhibition of reabsorption of Mg in renal tubules is one of the causes. In addition, recent reports have shown that long-term administration of proton pump inhibitors (PPIs) reduces serum magnesium levels. Therefore, in this study, 102 patients who received oral PPIs treated with panitumumab were classified into a PPI combination group and a PPI non-combination group, and the effect of PPIs on the development of grade 2 or higher hypomagnesemia was investigated. The incidence of hypomagnesemia in the PPI combination group (46.9%, 15/32) was higher than that in the PPI non-combination group (25.7%, 18/70). A comparison of the backgrounds of the two groups of patients showed a significant difference in serum albumin levels. PPI administration was significantly associated with panitumumab-induced hypomagnesemia development when adjusted for known risk factors, serum albumin level, renal function, and oral magnesium oxide tablets in Cox proportional hazards regression analysis (hazard ratio 2.09; 95% confidence interval 1.03-4.22; P =0.040). These results indicate that detailed monitoring of serum magnesium levels is recommended for patients treated with panitumumab and co-administration of PPIs.

Histological Analysis of Cartilage Defects Repaired with an Autologous Human Stem Cell Construct 48 Weeks Postimplantation Reveals Structural Details Not Detected by T2-Mapping MRI

OBJECTIVE

The aim of this study was to elucidate the efficacy of T2-mapping MRI and correlation with histology for the evaluation of tissue repair quality following the first-in-human implantation of an autologous tissue engineered construct.

DESIGN

We directly compared the results of T2-mapping MRI of cartilage repair tissue with the histology of a biopsy specimen from the corresponding area at 48 weeks postoperatively in 5 patients who underwent the implantation of a scaffold-free tissue-engineered construct generated from autologous synovial mesenchymal stem cells to repair an isolated cartilage lesion. T2 values and histological scores were compared at each of 2 layers of equally divided halves of the repair tissue (upper and lower zones).

RESULTS

Histology showed that the repair tissue in the upper zone was dominated by fibrous tissue and the ratio of hyaline-like matrix increased with the depth of the repair tissue. There were significant differences between upper and lower zones in histological scores. Conversely, there were no detectable statistically significant differences in T2 value detected among zones of the repair tissue, but zonal differences were detected in corresponding healthy cartilage. Accordingly, there were no correlations detected between histological scores and T2 values for each repair cartilage zone.

CONCLUSION

Discrepancies in the findings between T2 mapping and histology suggest that T2 mapping was limited in ability to detect details in the architecture and composition of the repair cartilage.

Suture Slippage During Anterior Cruciate Ligament Graft Passage Is Significantly Lower Using a Krackow Suture

Purpose

To compare the suture slippage on a hamstring tendon graft prepared with a modified finger-trap device (SPEEDTRAP) with one prepared with Krackow stitch during graft passage through the tibial tunnel in ACL reconstruction.

Methods

Thirty-eight patients underwent anatomic triple-bundle anterior cruciate ligament reconstruction with 2 femoral and 3 tibial tunnels. After semitendinosus tendon was cut in half to make 2 grafts, the free ends of the proximal membranous portion (posterolateral [PL] graft) were prepared together with 2 sutures: (1) one SPEEDTRAP and one Krackow stitch for 20 cases (group A) and (2) double Krackow stitches on both sides for 18 cases (group B). Then, the PL graft was dye-marked at the proximal suture of SPEEDTRAP in group A and Krackow suture in group B and was inserted into the joint via tibial tunnel ahead of the loop side. The distance between the mark on the graft and the proximal suture of SPEEDTRAP or Krackow stitch was measured under arthroscopy after graft fixation at femur. Slippage was defined as 1 mm and more of distance between the mark and the proximal suture.

Results

Slippage was observed in 16 cases for SPEEDTRAP and in 2 for Krackow suture in group A, whereas one case showed slippage in group B. The slippage distance was 4.0 ± 2.9 mm for SPEEDTRAP and 0.2 ± 0.5 mm for Krackow stitch in group A (P < .001), whereas it was 0.1 ± 0.2 mm for double Krackow stitch in group B, showing a significant difference from SPEEDTRAP suture (P < .001).

Conclusions

At the time of PL graft passage through the tibial tunnel in anterior cruciate ligament reconstruction, there was significantly less slippage observed with the Krackow stitch compared with the SPEEDTRAP stitch.

Level of Evidence

Level IV, therapeutic case series.

Barthel Index score predicts mortality in elderly heart failure: a goal of comprehensive cardiac rehabilitation

Background

Accurate prediction of mortality in heart failure (HF) patients is crucial for decision-making regarding HF therapies, but a strategy for the prediction of mortality in elderly HF patients has not been established. In addition, although favorable effects of comprehensive cardiac rehabilitation (CR) on clinical outcomes and functional status in HF patients have been demonstrated, a goal of comprehensive CR during hospitalization for reducing mortality remains unclear.

Aims

We examined whether assessment of basic activities of daily living (ADL) by the Barthel Index (BI), the most widely used tool for assessment of basic ADL, is useful for predicting all-cause mortality in elderly HF patients who received comprehensive CR.

Methods

This study was a single-center, retrospective and observational study. We retrospectively examined 413 HF patients aged ≥65 years (mean age, 78±7 years; 50% female) who were admitted to our institute for management of HF and received comprehensive CR during hospitalization. Functional status for performing basic ADL ability was assessed by the BI within 3 days before discharge. The clinical endpoint was all-cause death during the follow-up period.

Results

Of 413 HF patients, 116 patients (28%) died during a follow-up period of median 1.90-years (interquartile range, 1.20–3.23 years). Results of an adjusted dose-dependent association analysis showed that the hazard ratio (HR) of mortality increases in an almost linear fashion as the BI score decreases and that the BI score corresponding the hazard ratio of 1.0 is 85 (Figure A). To minimize the differences in potential confounding factors between patient with low BI (&lt;85) and patients with high BI (≥85), inverse probability treatment weighting (IPTW) was calculated using propensity score. Kaplan-Meier survival curves, in which selection bias was minimized by use of IPTW for confounders, showed that patients with low BI (&lt;85) had a higher mortality rate than did patients with high BI (≥85) (Figure B). In multivariate Cox regression analyses, low BI was independently associated with higher mortality after adjustment for predictors including brain natriuretic peptide and prior HF hospitalization (IPTW-adjusted HR, 1.75 [95% confidence interval, 1.03–2.98], p&lt;0.001). Inclusion of the BI into the adjustment model improved the accuracy of prediction of mortality (continuous net reclassification improvement, 0.292, p=0.008; integrated discrimination improvement, 0.017, p=0.022).

Conclusion

A BI score of &lt;85 at the time of discharge is associated with increased mortality independently of known prognostic markers, and achievement of functional status of a BI score ≥85 by comprehensive CR during hospitalization may contribute to a favorable outcome in elderly HF patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): the Japan Society for the Promotion of Science

Deexcitation Dynamics of Muonic Atoms Revealed by High-Precision Spectroscopy of Electronic K X Rays

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kβ x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

Return to the original sport at only 3 months after an Achilles tendon rupture by a combination of intra-tissue injection of freeze-dried platelet-derived factor concentrate and excessively early rehabilitation after operative treatment in a male basketball player: A case report

Background

Achilles tendon rupture is one of the most common serious injuries in athletes. Various studies to accelerate the healing process of the Achilles tendon have been performed as it takes a longer time to repair the tissue compared to other tendons. Here, we report a case of an acute Achilles tendon rupture in a male basketball player treated by a combination of an intra-tissue injection of freeze-dried platelet-derived factor concentrate, which included a platelet-derived growth factor with an early rehabilitation protocol after the operative treatment to facilitate the biological healing of the injured tendon tissue. To the best of our knowledge, this case is the first instance that enabled the athlete to return to original sport activity at only 3-months after the injury.

Case report

A 23-year-old male basketball player who belonged to a university basketball team sustained an Achilles tendon rupture during running in a training match. The remaining time period until the final tournament of the university league as a senior player was only 3 months. The patient received a combination of an intra-tissue injection of freeze-dried platelet-derived factor concentrate and early rehabilitation protocol after operative treatment. Surgery was performed 4 days after the injury and the early rehabilitation protocols were applied postoperatively. A freeze-dried platelet-derived factor concentrate was injected into the ruptured site of the Achilles tendon under ultrasound guide at 4 weeks postoperatively. The patient could return to play at the pre-injury level without any symptoms and disfunctions at 3 months after surgery. At two years postoperatively, the patient could play basketball without symptoms or rerupture.

Conclusions

We reported a case of an Achilles tendon rupture which was treated by a combination of intra-tissue injection of freeze-dried platelet-derived factor concentrate and an early rehabilitation protocol after the operative treatment. The patient could return to play basketball at the pre-injury activity level at only 3-months after the injury, suggesting that the role of applying excessively early rehabilitation of mechanical loading could facilitate tendon tissue healing when combined with an intra-tissue injection of freeze-dried platelet-derived factor concentrate.

•

FD-PFC has rich growth factors such as PDGF-BB, which is a part of the PDGF growth family.

•

An achilles tendon rupture was treated by a combination of injection of FD-PFC and excessively postoperative rehabilitation.

•

The patient could return to play basketball at the pre-injury activity level at only 3-months after the injury.

Perifosine enhances the potential antitumor effect of 5-fluorourasil and oxaliplatin in colon cancer cells harboring the PIK3CA mutation

Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) mutation in colon cancer contributes to the poor prognosis of the disease and chemoresistance of tumors. New therapies are needed; however, the lack of knowledge of the mechanism of chemoresistance has hindered progress. In this study, we investigated the mechanism of the reduced sensitivity of colon cancer cells to 5-fluorouracil (5-FU) and oxaliplatin (L-OHP), and the effects of perifosine, an Akt inhibitor that enhances the cytotoxicity of 5-FU and L-OHP in colon cancer cells harboring the PIK3CA mutation. The use of 5-FU or L-OHP alone or in combination induced significant death of Caco-2 cells (PIK3CA wild type), but only weakly decreased the viability of DLD-1 and SW948 cells harboring the PIK3CA mutation. The use of 5-FU and L-OHP, either alone or in combination, strongly suppressed Akt activation, Survivin, Bcl-2, and Bcl-xL expression, and enhanced Puma, phospho-p53, and p53 expression in Caco-2 cells than in DLD-1 cells. In addition, perifosine enhanced the cytotoxicity of the 5-FU and L-OHP combination, inhibited Akt activation and the expression of Survivin, Bcl-2, and Bcl-xL, and increased the expression of Puma, phospho-p53, and p53 in DLD-1 cells. These results indicate that PIK3CA mutation contributes to reduced sensitivity to 5-FU and L-OHP via Akt activation in colon cancer cells. Perifosine increases the efficacy of 5-FU and L-OHP by suppressing Akt activation. Thus, the use of an Akt inhibitor in combination with 5-FU and L-OHP may be beneficial in colon cancer with cells harboring the PIK3CA mutation.

Rhosin Suppressed Tumor Cell Metastasis through Inhibition of Rho/YAP Pathway and Expression of RHAMM and CXCR4 in Melanoma and Breast Cancer Cells

The high mortality rate of cancer is strongly correlated with the development of distant metastases at secondary sites. Although Rho GTPases, such as RhoA, RhoB, RhoC, and RhoE, promote tumor metastasis, the main roles of Rho GTPases remain unidentified. It is also unclear whether rhosin, a Rho inhibitor, acts by suppressing metastasis by a downstream inhibition of Rho. In this study, we investigated this mechanism of metastasis in highly metastatic melanoma and breast cancer cells, and the mechanism of inhibition of metastasis by rhosin. We found that rhosin suppressed the RhoA and RhoC activation, the nuclear localization of YAP, but did not affect ERK1/2, Akt, or NF-κB activation in the highly metastatic cell lines B16BL6 and 4T1. High expression of YAP was associated with poor overall and recurrence-free survival in patients with breast cancer or melanoma. Treatment with rhosin inhibited lung metastasis in vivo. Moreover, rhosin inhibited tumor cell adhesion to the extracellular matrix via suppression of RHAMM expression, and inhibited SDF-1-induced cell migration and invasion by decreasing CXCR4 expression in B16BL6 and 4T1 cells. These results suggest that the inhibition of RhoA/C-YAP pathway by rhosin could be an extremely useful therapeutic approach in patients with melanoma and breast cancer.

Potential of Soluble Decellularized Extracellular Matrix for Musculoskeletal Tissue Engineering - Comparison of Various Mesenchymal Tissues

Background

It is well studied that preparations of decellularized extracellular matrix (ECM) obtained from mesenchymal tissues can function as biological scaffolds to regenerate injured musculoskeletal tissues. Previously, we reported that soluble decellularized ECMs derived from meniscal tissue demonstrated excellent biocompatibility and produced meniscal regenerate with native meniscal anatomy and biochemical characteristics. We therefore hypothesized that decellularized mesenchymal tissue ECMs from various mesenchymal tissues should exhibit tissue-specific bioactivity. The purpose of this study was to test this hypothesis using porcine tissues, for potential applications in musculoskeletal tissue engineering.

Methods

Nine types of porcine tissue, including cartilage, meniscus, ligament, tendon, muscle, synovium, fat pad, fat, and bone, were decellularized using established methods and solubilized. Although the current trend is to develop tissue specific decellularization protocols, we selected a simple standard protocol across all tissues using Triton X-100 and DNase/RNase after mincing to compare the outcome. The content of sulfated glycosaminoglycan (sGAG) and hydroxyproline were quantified to determine the biochemical composition of each tissue. Along with the concentration of several growth factors, known to be involved in tissue repair and/or maturation, including bFGF, IGF-1, VEGF, and TGF-β1. The effect of soluble ECMs on cell differentiation was explored by combining them with 3D collagen scaffold culturing human synovium derived mesenchymal stem cells (hSMSCs).

Results

The decellularization of each tissue was performed and confirmed both histologically [hematoxylin and eosin (H&E) and 4’,6-diamidino-2-phenylindole (DAPI) staining] and on the basis of dsDNA quantification. The content of hydroxyproline of each tissue was relatively unchanged during the decellularization process when comparing the native and decellularized tissue. Cartilage and meniscus exhibited a significant decrease in sGAG content. The content of hydroxyproline in meniscus-derived ECM was the highest when compared with other tissues, while sGAG content in cartilage was the highest. Interestingly, a tissue-specific composition of most of the growth factors was measured in each soluble decellularized ECM and specific differentiation potential was particularly evident in cartilage, ligament and bone derived ECMs.

Conclusion

In this study, soluble decellularized ECMs exhibited differences based on their tissue of origin and the present results are important going forward in the field of musculoskeletal regeneration therapy.

Evidence that TD-198946 enhances the chondrogenic potential of human synovium-derived stem cells through the NOTCH3 signaling pathway

Human synovium-derived stem cells (hSSCs) are an attractive source of cells for cartilage repair. At present, the quality of tissue and techniques used for cartilage regeneration have scope for improvement. A small compound, TD-198946, was reported to enhance chondrogenic induction from hSSCs; however, other applications of TD-198946, such as priming the cell potential of hSSCs, remain unknown. Our study aimed to examine the effect of TD-198946 pretreatment on hSSCs. HSSCs were cultured with or without TD-198946 for 7 days during expansion culture and then converted into a three-dimensional pellet culture supplemented with bone morphogenetic protein-2 (BMP2) and/or transforming growth factor beta-3 (TGFβ3). Chondrogenesis in cultures was assessed based on the GAG content, histology, and expression levels of chondrogenic marker genes. Cell pellets derived from TD-198946-pretreated hSSCs showed enhanced chondrogenic potential when chondrogenesis was induced by both BMP2 and TGFβ3. Moreover, cartilaginous tissue was efficiently generated from TD-198946-pretreated hSSCs using a combination of BMP2 and TGFβ3. Microarray analysis revealed that NOTCH pathway-related genes and their target genes were significantly upregulated in TD-198946-treated hSSCs, although TD-198946 alone did not upregulate chondrogenesis related markers. The administration of the NOTCH signal inhibitor diminished the effect of TD-198946. Thus, TD-198946 enhances the chondrogenic potential of hSSCs via the NOTCH3 signaling pathway. This study is the first to demonstrate the gradual activation of NOTCH3 signaling during chondrogenesis in hSSCs. The priming of NOTCH3 using TD-198946 provides a novel insight regarding the regulation of the differentiation of hSSCs into chondrocytes.

Osteochondral Injury, Management and Tissue Engineering Approaches

Osteochondral lesions (OL) are a common clinical problem for orthopedic surgeons worldwide and are associated with multiple clinical scenarios ranging from trauma to osteonecrosis. OL vary from chondral lesions in that they involve the subchondral bone and chondral surface, making their management more complex than an isolated chondral injury. Subchondral bone involvement allows for a natural healing response from the body as marrow elements are able to come into contact with the defect site. However, this repair is inadequate resulting in fibrous scar tissue. The second differentiating feature of OL is that damage to the subchondral bone has deleterious effects on the mechanical strength and nutritive capabilities to the chondral joint surface. The clinical solution must, therefore, address both the articular cartilage as well as the subchondral bone beneath it to restore and preserve joint health. Both cartilage and subchondral bone have distinctive functional requirements and therefore their physical and biological characteristics are very much dissimilar, yet they must work together as one unit for ideal joint functioning. In the past, the obvious solution was autologous graft transfer, where an osteochondral bone plug was harvested from a non-weight bearing portion of the joint and implanted into the defect site. Allografts have been utilized similarly to eliminate the donor site morbidity associated with autologous techniques and overall results have been good but both techniques have their drawbacks and limitations. Tissue engineering has thus been an attractive option to create multiphasic scaffolds and implants. Biphasic and triphasic implants have been under explored and have both a chondral and subchondral component with an interface between the two to deliver an implant which is biocompatible and emulates the osteochondral unit as a whole. It has been a challenge to develop such implants and many manufacturing techniques have been utilized to bring together two unalike materials and combine them with cellular therapies. We summarize the functions of the osteochondral unit and describe the currently available management techniques under study.

The HGF/Met/NF-κB Pathway Regulates RANKL Expression in Osteoblasts and Bone Marrow Stromal Cells

Multiple myeloma (MM)-induced bone disease occurs through hyperactivation of osteoclasts by several factors secreted by MM cells. MM cell-secreted factors induce osteoclast differentiation and activation via direct and indirect actions including enhanced expression of receptor activator of nuclear factor κB ligand (RANKL) in osteoblasts and bone marrow stromal cells (BMSCs). Hepatocyte growth factor (HGF) is elevated in MM patients and is associated with MM-induced bone disease, although the mechanism by which HGF promotes bone disease remains unclear. In the present study, we demonstrated that HGF induces RANKL expression in osteoblasts and BMSCs, and investigated the mechanism of induction. We found that HGF and MM cell supernatants induced RANKL expression in ST2 cells, MC3T3-E1 cells, and mouse BMSCs. In addition, HGF increased phosphorylation of Met and nuclear factor κB (NF-κB) in ST2 cells, MC3T3-E1 cells, or mouse BMSCs. Moreover, Met and NF-κB inhibitors suppressed HGF-induced RANKL expression in ST2 cells, MC3T3-E1 cells, and mouse BMSCs. These results indicated that HGF promotes RANKL expression in osteoblasts and BMSCs via the Met/NF-κB signaling pathway, and Met and NF-κB inhibitors suppressed HGF-induced RANKL expression. Our findings suggest that Met and NF-κB inhibitors are potentially useful in mitigating MM-induced bone disease in patients expressing high levels of HGF.

Current hip cartilage regeneration/repair modalities: a scoping review of biologics and surgery

PURPOSE

The rapidly growing and emerging nature of biologics have made indications for regenerative and reparative hip therapies ever changing, with at times only early-stage evidence for their use. The purpose of this study was to review and summarize the currently available data on the management of hip cartilage injuries and osteoarthritis.

METHODS

A scoping review of the available scientific literature for hip biologics was performed, with available evidence for hyaluronic acid (HA), platelet rich plasma (PRP), stem/stromal cells, microfracture, mosaicplasty, osteochondral allograft, and cell-based therapies investigated.

RESULTS

To date, there exist better guidelines and further consensus concerning knee joint biologic treatments than the hip due to a greater number of studies as well as the more recent emergence of hip preservation approaches. However, increasing evidence is available for the selective implementation of biologics on an individualized basis with attention to lesion size and location.

CONCLUSION

Orthopedic surgeons are at an exciting crossroads in medicine, where hip biologic therapies are evolving and increasingly available. Timetested interventions such as arthroplasty have shown good results and still have a major role to play but newer, regenerative approaches have the potential to effectively delay or reduce the requirement for such invasive procedures.

Human Synovial Mesenchymal Stem Cells Good Manufacturing Practices for Articular Cartilage Regeneration

Background: Cartilage restoration is a desperately needed bridge for patients with symptomatic cartilage lesions. Chondral lesion is a pathology with high prevalence, reaching as much as 63% of general population and 36% among athletes. Despite autologous chondrocyte implantation versatility, it still fails to fully reproduce hyaline articular cartilage characteristics. Mesenchymal stem cells (MSCs) may be isolated from various known tissues, including discarded fragments at arthroscopy such as synovial membrane. Choice of harvesting site is motivated by MSCs' abilities to modulate immunologic and inflammatory response through paracrine communication. Synovial MSCs have a greater proliferation and strong chondrogenic potential than bone and adipose MSCs and a less hypertrophic differentiation than bone MSCs. Good manufacturing practice (GMP) laboratory techniques for human clinical trials are still novel. To our knowledge, there are only two clinical trials in humans published since today. Purpose: Therefore, this work aimed to isolate and characterize synovial MSCs and evaluated their differentiation properties according to GMP standards. Materials and Methods: One-gram tissue sample from three patients of synovia was harvested at the beginning of arthroscopy surgery. MSCs were isolated, expanded, and characterized by flow cytometry. Results: It was possible to isolate and expand MSCs cultures from synovia, characterize MSCs by flow cytometry using proper monoclonal antibodies, and differentiate MSCs by coloring technique after chondrogenic, adipogenic, and osteogenic differentiations. Cartilage treatment may benefit from these tissue engineering protocols since arthroscopic procedures are routinely performed for different purposes in a previous stage and a favorable chondronegic differentiation cell lineage may be collected and stored in a less invasive way. Conclusion: Laboratory protocols established according to presented GMP were able to isolate and characterize MSCs obtained from synovia. Impact Statement Articular cartilage restoration is a desperately needed bridge for patients with symptomatic cartilage lesions and it rises as a socioeconomic issue with a considerable economic burden. Synovial mesenchymal stem cells (MSCs) have a greater proliferation rate and strong chondrogenic potential than bone and adipose MSCs and a less hypertrophic differentiation than bone MSCs. To our knowledge, there are only two human clinical trials with good manufacturing practice laboratory techniques for synovial MSCs harvesting and differentiation. Cartilage treatment may benefit from these tissue engineering protocols since arthroscopic procedures are routinely performed for different purposes in a previous stage.

0103 Novel Prebiotic Enhances Sleep-Wake Cycle and Memory Consolidation in 5xFAD Mice

Introduction

Prior studies have shown that the gut microbiomes of Alzheimer’s Disease (AD) patients differ from unaffected individuals. Sleep and circadian rhythm disturbances are common in AD and often precede dementia symptoms. Gut microbiome alterations have also been observed in models of circadian disruption. Therefore, we hypothesized that altering the gut microbiome could improve sleep/circadian rhythms and cognition in an AD mouse model.

Methods

Mice were given a dietary polysaccharide, Modified Resistant Maltodextrin (MRM), as a 1% solution in the drinking water beginning at 2 months of age. 5xFAD and wild-type (WT) littermates were tested. Sleep-wake was recorded by EEG/EMG, memory consolidation was tested by the Object-Location Memory test, and beta amyloid deposition in the brain was assayed (dot blot). Composition of the gut microbiota was determined from amplicon sequencing of the 16s ribosomal RNA gene from fecal DNA.

Results

MRM treatment reduced dark (active)-phase sleep and the phase scattering of REM sleep in 5xFAD mice, indices of circadian consolidation. 6-month-old 5xFAD mice given plain water exhibited no 24hr retention of object location memory. However, MRM-treated 5xFAD mice demonstrated 24-hour memory, even at 12 months of age. Both improved memory and increased consolidation of sleep were also observed in WT mice. Two unclassified species of bacteria from the family Tannerellaceae were significantly increased in MRM-treated 5xFAD and WT mice. At 12 months of age, synaptic and neuronal loss become prominent in this AD model. However, the level of beta amyloid deposition in the brain was not significantly different between MRM and water control groups.

Conclusion

MRM treatment altered the gut microbiome, improved circadian timing of sleep and memory retention, but did not impact beta amyloid deposition in 5xFAD mice. Because these effects were also present in WT mice, MRM-induced microbiome changes may affect sleep and cognition independently from beta amyloid.

Support

Northwestern University Feinberg School of Medicine Center for Circadian and Sleep Medicine

Enhancement of chondrogenic differentiation supplemented by a novel small compound for chondrocyte-based tissue engineering

Purpose

Chondrocyte -based tissue engineering has been a promising option for the treatment of cartilage lesions. In previous literature, TD198946 has been shown to promote chondrogenic differentiation which could prove useful in cartilage regeneration therapies. Our study aimed to investigate the effects of TD198946 in generating engineered cartilage using dedifferentiated chondrocyte-seeded collagen scaffolds treated with TD198946.

Methods

Articular chondrocytes were isolated from mini pig knees and expanded in 2-dimensional cell culture and subsequently used in the experiments. 3-D pellets were then cultured for two weeks. Cells were also cultured in a type I collagen scaffolds for four weeks. Specimens were cultured with TD198946, BMP-2, or both in combination. Outcomes were determined by gene expression levels of RUNX1, SOX9, ACAN, COL1A1, COL2A1 and COL10A1, the glycosaminoglycan content, and characteristics of histology and immunohistochemistry. Furthermore, the maturity of the engineered cartilage cultured for two weeks was evaluated through subcutaneous implantation in nude mice for four weeks.

Results

Addition of TD198946 demonstrated the upregulation of gene expression level except for ACAN, type II collagen and glycosaminoglycan synthesis in both pellet and 3D scaffold cultures. TD198946 and BMP-2 combination cultures showed higher chondrogenic differentiation than TD198946 or BMP-2 alone. The engineered cartilage maintained its extracellular matrices for four weeks post implantation. In contrast, engineered cartilage treated with either TD198946 or BMP-2 alone was mostly absorbed.

Conclusions

Our results indicate that TD198946 could improve quality of engineered cartilage by redifferentiation of dedifferentiated chondrocytes pre-implantation and promoting collagen and glycosaminoglycan synthesis.

Vibration acceleration promotes endochondral formation during fracture healing through cellular chondrogenic differentiation

Vibration acceleration through whole body vibration has been reported to promote fracture healing. However, the mechanism responsible for this effect remains unclear. Purpose of this study was to determine whether vibration acceleration directly affects cells around the fracture site and promotes endochondral ossification. Four-week-old female Wistar Hannover rats were divided into two groups (vibration [V group] and control [C group]). The eighth ribs on both sides were cut vertically using scissors. From postoperative day 3 to 11, vibration acceleration using Power Plate^® (30 Hz, low amplitude [30-Low], 10 min/day) was applied in the V group. Mature calluses appeared earlier in the V group than in the C group by histological analysis. The GAG content in the fracture callus on day 6 was significantly higher in the V group than in the C group. The mRNA expressions of SOX-9, aggrecan, and Col-II in the fracture callus on day 6 and Col-X on day 9 were significantly higher in the V group than in the C group. For in vitro analysis, four different conditions of vibration acceleration (30 or 50 Hz with low or high amplitude [30-Low, 30-High, 50-Low, and 50-High], 10 min/day) were applied to a prechondrogenic cell (ATDC5) and an undifferentiated cell (C3H10T1/2). There was no significant difference in cell proliferation between the control and any of the four vibration conditions for both cell lines. For both cell lines, alcian blue staining was greater under 30-Low and 50-Low conditions than under control as well as 30-High and 50-High conditions on days 7 and 14. Vibration acceleration under 30-L condition upregulated chondrogenic gene expressions of SOX-9, aggrecan, Col-II, and Col-X. Low-amplitude vibration acceleration can promote endochondral ossification in the fracture healing in vivo and chondrogenic differentiation in vitro.

The Meniscus Tear: A Review of Stem Cell Therapies

Meniscal injuries have posed a challenging problem for many years, especially considering that historically the meniscus was considered to be a structure with no important role in the knee joint. This led to earlier treatments aiming at the removal of the entire structure in a procedure known as a meniscectomy. However, with the current understanding of the function and roles of the meniscus, meniscectomy has been identified to accelerate joint degradation significantly and is no longer a preferred treatment option in meniscal tears. Current therapies are now focused to regenerate, repair, or replace the injured meniscus to restore its native function. Repairs have improved in technique and materials over time, with various implant devices being utilized and developed. More recently, strategies have applied stem cells, tissue engineering, and their combination to potentiate healing to achieve superior quality repair tissue and retard the joint degeneration associated with an injured or inadequately functioning meniscus. Accordingly, the purpose of this current review is to summarize the current available pre-clinical and clinical literature using stem cells and tissue engineering for meniscal repair and regeneration.

Overactivation of Akt Contributes to MEK Inhibitor Primary and Acquired Resistance in Colorectal Cancer Cells

RAS and BRAF-mutated colorectal cancers are associated with resistance to chemotherapy and poor prognosis, highlighting the need for new therapeutic strategies. Although these cancers sometimes respond to mitogen activated protein kinase kinase (MEK) inhibitor treatment, they often acquire resistance via mechanisms, which are poorly understood. Here, we investigated the mechanism of MEK inhibitor resistance in primary- and acquired-resistant cells. Cell viability was examined using the trypan blue dye exclusion assay. Protein expression was analyzed by western blotting. Somatic mutations in colorectal cancer cells were investigated using the polymerase chain reaction array. PD0325901 and trametinib induced cell death in LoVo and Colo-205 cells but not in DLD-1 and HT-29 cells, which have a PIK3CA mutation constitutively activating Akt and NF-κB. Treatment with PD0325901 and trametinib suppressed ERK1/2 activation in all four cell lines but only induced Akt and NF-κB activation in DLD-1 and HT-29 cells. Inhibition of Akt but not NF-κB, overcame MEK inhibitor resistance in DLD-1 and HT-29 cells. Acquired-resistant LoVo/PR, Colo-205/PR and LoVo/TR cells have constitutively active Akt due to a M1043V mutation in the kinase activation loop of PIK3CA and Akt inhibitor resensitized these cells to MEK inhibitor. These results demonstrate that the overactivation of Akt plays a critical role in MEK inhibitor primary and acquired resistance and implicate combined Akt/MEK inhibition as a potentially useful treatment for RAS/BRAF-mutated colorectal cancer.

P4537Impact of body composition analysis on prediction of short-term readmission events in heart failure: muscle wasting vs. obesity

Background

Obesity, defined as higher body mass index (BMI), is associated with better prognosis in patients with chronic heart failure (CHF), though the presence of obesity is a risk factor of development of CHF (Obesity paradox). On the other hand, muscle wasting, i.e. reduction in skeletal muscle mass, is frequently observed in CHF, leading to lower exercise capacity and poor cardiovascular outcome.

Purpose

The aim of this study was to examine whether analysis of body composition improves prediction of short-term readmission rates in patients with CHF.

Methods

We retrospectively analyzed data for 167 consecutive HF patients who were admitted to our institute for management of HF and received a Dual-energy X-ray absorptiometry (DEXA) scan. Muscle wasting was defined as DEXA-measured appendicular skeletal muscle mass index <7.0 kg/m2 in male and <5.4 kg/m2 in female according to the Asian Working Group for Sarcopenia criteria. Obesity was defined according to the criteria by the use of DEXA-measured percent body fat mass: >25% in male, >30% in female. The primary endpoint was readmission due to cardiac events including worsening heart failure, arrhythmia, and cardiopulmonary arrest during a 180-days follow-up period after discharge.

Results

The mean age of the patients was 74±13 years and 46% of them were male. The mean BMI was 21.8±3.8 kg/m2. Forty-seven percent of the patients were classified as NYHA functional class III. The most frequent etiology of HF was cardiomyopathy (30%), followed by ischemic heart disease (27%) and valvular heart disease (27%). The prevalence of muscle wasting and that of obesity were 69% and 59%, respectively. Patients with muscle wasting had lower BMI level, higher prevalence of NYHA functional class III and diabetes mellitus compared with those without muscle wasting. On the other hand, patients with obesity had higher prevalence of hypertension and dyslipidemia, higher level of BMI, fasting plasma insulin and triglyceride, and lower level of HDL-cholesterol compared with those without obesity. During the follow-up period, 34 patients (19%) were re-hospitalized due to cardiac events. Kaplan-Meier survival curves showed that patients with obesity had a significantly lower readmission rate during a 180-days follow-up period than did the patients without obesity (14.3% vs. 29.0%, Log-Rank test, p<0.01). There was no difference in readmission rates between patients with and without muscle wasting (20.0% vs. 21.2%, p=0.88). In multivariate Cox regression analyses adjusted for age, sex, diabetes, and renal function, obesity was independently associated with lower readmission rates (hazard ratio 0.45, 95% confidence interval 0.22–0.93). However, the association between obesity and readmission rate was lost after the adjustment for NT-proBNP levels.

Conclusion

Body composition analysis by DEXA enables to find CHF patients with increased fat mass who have lower risk of short-term readmission.

P1538Low energy intake predicts readmission of elderly heart failure patients independently of nutritional status

Background

Malnutrition is frequently present and closely associated with poor clinical outcomes in elderly heart failure (HF) patients. Our previous study showed that low energy intake (EI) is associated with worse functional status in elderly HF inpatients after cardiac rehabilitation, but significance of EI in prediction of hospital readmission has not been elucidated fully.

Purpose

We examined whether low EI is a predictor of readmission for cardiac events in elderly HF patients.

Methods

We retrospectively retrieved data for 298 HF patients aged ≥65 years (median age of 77 years, interquartile range [IQR]: 71 - 82, female: 53%) who admitted to our institute for diagnosis and treatment of HF. Medical records were reviewed with regard to demography, medical history, comorbidities, medications, laboratory data, echocardiograms, functional status, nutritional status and total energy intake. Nutritional status was assessed using the Mini Nutritional Assessment Short Form (MNA-SF) and total EI per day were calculated at discharge by a registered dietitian and a trained physical therapist. The primary endpoint was readmission due to cardiovascular events including worsening HF, arrhythmia, angina pectoris and myocardial infarction during a 1-year follow-up period.

Results

The median period of follow-up was 235 days (IQR: 78–365 days). The 1-year readmission rate for cardiovascular events was 54.4%. The cutoff values of MNA-SF score and EI, calculated by ROC curve analysis to predict the primary endpoint, were 7 points (area under the curve [AUC]: 0.59, sensitivity: 0.65, specificity: 0.50) and 31.8 kcal/kg/day (AUC: 0.59, sensitivity: 0.83, specificity: 0.35), respectively. Patients with low MNF-SF score (≤7) or low EI (≤31.8 kcal/kg/day) had significantly higher readmission rate during a 1-year follow-up period than did the patients with high MNF-SF score or EI (MNA-SF: 60.7% vs. 45.6%, p<0.01, EI: 60.4% vs. 36.8%, p<0.01), respectively. When patients were classified into four groups using cutoff values of MNA-SF score and EI, 1-year readmission rate was significantly higher in patients with low EI than in those with high EI regardless of MNF-SF scores. In multivariate Cox proportional hazard analyses adjusted for known prognostic factors in addition to age and gender, hazard ratios (HR) were significantly higher in patients with high MNA-SF score and low EI (adjusted HR: 2.81, 95% confidential interval [CI]: 1.15 - 9.32, p=0.02) and low MNA-SF score (≤7) and low EI (adjusted HR: 4.16, 95% CI: 1.72 - 13.72, p<0.01) than those with high MNA-SF score and high EI.

Kaplan-Meier curves of readmission rates

Conclusions

Low energy intake is a nutritional status-independent predictor of 1-year readmission rate in elderly HF patients.

Comparative Clinical Outcomes After Intra-articular Injection With Adipose-Derived Cultured Stem Cells or Noncultured Stromal Vascular Fraction for the Treatment of Knee Osteoarthritis

BACKGROUND

Intra-articular injection of adipose-derived stem cells (ASCs) has shown promise for improving symptoms and cartilage quality in the treatment of osteoarthritis (OA). However, while most preclinical studies have been performed with plastic-adherent ASCs, most clinical trials are being conducted with the stromal vascular fraction (SVF), prepared from adipose tissue without prior culture.

PURPOSE

To directly compare clinical outcomes of intra-articular injection with ASCs or SVF in patients with knee OA.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The authors retrospectively compared 6-month outcomes in 42 patients (59 knees) receiving intra-articular injection with 12.75 million ASCs and 38 patients (69 knees) receiving a 5-mL preparation of SVF. All patients had Kellgren-Lawrence grade 2, 3, or 4 knee OA and had failed standard medical therapy. The visual analog scale (VAS) pain score and Knee injury and Osteoarthritis Outcome Score (KOOS) at baseline and 1, 3, and 6 months after injection were considered as outcomes. Outcome Measures in Rheumatology-Osteoarthritis Research Society International (OMERACT-OARSI) criteria were also used to assess positive response. A repeated measures analysis of variance was used for comparison between the treatment groups.

RESULTS

No major complications occurred in either group. The SVF group had a higher frequency of knee effusion (SVF 8%, ASC 2%) and minor complications related to the fat harvest site (SVF 34%, ASC 5%). Both groups reported improvements in pain VAS and KOOS domains. Specifically, in the ASC group, symptoms improved earlier (by 3 months; P < .05) and pain VAS decreased to a greater degree (55%; P < .05) compared with the SVF group (44%). The proportion of OMERACT-OARSI responders in the ASC group was slightly higher (ASCs, 61%; SVF, 55%; P = .25).

CONCLUSION

It was observed that both ASCs and SVF resulted in clinical improvement in patients with knee OA, but that ASCs outperform SVF in the early reduction of symptoms and pain with less comorbidity.

Optimization of photocrosslinked gelatin/hyaluronic acid hybrid scaffold for the repair of cartilage defect

There is no therapy currently available for fully repairing articular cartilage lesions. Our laboratory has recently developed a visible light-activatable methacrylated gelatin (mGL) hydrogel, with the potential for cartilage regeneration. In this study, we further optimized mGL scaffolds by supplementing methacrylated hyaluronic acid (mHA), which has been shown to stimulate chondrogenesis via activation of critical cellular signalling pathways. We hypothesized that the introduction of an optimal ratio of mHA would enhance the biological properties of mGL scaffolds and augment chondrogenesis of human bone marrow-derived mesenchymal stem cells (hBMSCs). To test this hypothesis, hybrid scaffolds consisting of mGL and mHA at different weight ratios were fabricated with hBMSCs encapsulated at 20 × 106  cells/ml and maintained in a chondrogenesis-promoting medium. The chondrogenenic differentiation of hBMSCs, within different scaffolds, was estimated after 8 weeks of culture. Our results showed that mGL/mHA at a 9:1 (%, w/v) ratio resulted in the lowest hBMSC hypertrophy and highest glycosaminoglycan production, with a slightly increased volume of the entire construct. The applicability of this optimally designed mGL/mHA hybrid scaffold for cartilage repair was then examined in vivo. A full-thickness cylindrical osteochondral defect was surgically created in the rabbit femoral condyle, and a three-dimensional cell-biomaterial construct was fabricated by in situ photocrosslinking to fully fill the lesion site. The results showed that implantation of the mGL/mHA (9:1) construct resulted in both cartilage and subchondral bone regeneration after 12 weeks, supporting its use as a promising scaffold for repair and resurfacing of articular cartilage defects, in the clinical setting.

New precise measurements of muonium hyperfine structure at J-PARC MUSE

High precision measurements of the ground state hyperfine structure (HFS) of muonium is a stringent tool for testing bound-state quantum electrodynamics (QED) theory, determining fundamental constants of the muon magnetic moment and mass, and searches for new physics. Muonium is the most suitable system to test QED because both theoretical and experimental values can be precisely determined. Previous measurements were performed decades ago at LAMPF with uncertainties mostly dominated by statistical errors. At the J-PARC Muon Science Facility (MUSE), the MuSEUM collaboration is planning complementary measurements of muonium HFS both at zero and high magnetic field. The new high-intensity muon beam that will soon be available at H-Line will provide an opportunity to improve the precision of these measurements by one order of magnitude. An overview of the different aspects of these new muonium HFS measurements, the current status of the preparation for high-field measurements, and the latest results at zero field are presented.

Development of a Novel Large Animal Model to Evaluate Human Dental Pulp Stem Cells for Articular Cartilage Treatment

Purpose

Chondral lesion is a pathology with high prevalence, reaching as much as 63% of general population and 36% among athletes. The ability of human Dental Pulp Stem Cells (DPSCs) to differentiate into chondroblasts in vitro suggests that this stem cell type may be useful for tissue bioengineering. However, we have yet to identify a study of large animal models in which DPSCs were used to repair articular cartilage. Therefore, this study aimed to describe a novel treatment for cartilage lesion with DPSCs on a large animal model.

Methods

Mesenchymal stem cells (MSC) were obtained from deciduous teeth and characterized by flow cytometry. DPSCs were cultured and added to a collagen type I/III biomaterial composite scaffold. Brazilian miniature pig (BR-1) was used. A 6-mm diameter, full-thickness chondral defect was created in each posterior medial condyle. The defects were covered with scaffold alone or scaffold + DPSCs on the contralateral side. Animals were euthanized 6 weeks post-surgery. Cartilage defects were analyzed macroscopically and histology according to modified O’Driscoll scoring system.

Results

Flow cytometry confirmed characterization of DPSCs as MSCs. Macroscopic and histological findings suggested that this time period was reasonable for evaluating cartilage repair. To our knowledge, this study provides the first description of an animal model using DPSCs to study the differentiation of hyaline articular cartilage in vivo.

Conclusion

The animals tolerated the procedure well and did not show clinical or histological rejection of the DPSCs, reinforcing the feasibility of this descriptive miniature pig model for pre-clinical studies.

Enhanced repair of meniscal hoop structure injuries using an aligned electrospun nanofibrous scaffold combined with a mesenchymal stem cell-derived tissue engineered construct

Damage to the meniscal hoop structure results in loss of biomechanical function, which potentially leads to the extrusion of the meniscus from the weight bearing area. However, there have been no established, effective treatments for such injuries. The purpose of this study was to investigate the applicability of cell-seeded nanofibrous scaffolds to repair the damaged meniscal hoop structure along with the prevention of subsequent cartilage degeneration using a rabbit model. Meniscal radial defects (5 mm width) in the medial meniscus were treated by wrapping and suturing with either an aligned electrospun nanofibrous scaffold alone or a scaffold combined with a tissue engineered construct (TEC) derived from synovial mesenchymal stem cells (MSCs), with the scaffold fiber direction matching that of the meniscal circumferential fibers. The MSC-based TEC-combined nanofibrous scaffolds contributed significantly to the prevention of meniscal extrusion and exerted a chondroprotective effect, compared with either scaffold alone or the untreated control groups. Also, meniscal defects treated with such TEC-combined nanofibrous scaffolds were consistently repaired with a fibrocartilaginous tissue. In this study, we have demonstrated the feasibility of a combined TEC-nanofibrous scaffold to repair the meniscal hoop structure, and prevent the progression to cartilage degeneration, as a potential tissue engineering method.

First-in-Human Pilot Study of Implantation of a Scaffold-Free Tissue-Engineered Construct Generated From Autologous Synovial Mesenchymal Stem Cells for Repair of Knee Chondral Lesions

BACKGROUND

Articular cartilage has limited healing capacity, owing in part to poor vascularity and innervation. Once injured, it cannot be repaired, typically leading to high risk for developing osteoarthritis. Thus, cell-based and/or tissue-engineered approaches have been investigated; however, no approach has yet achieved safety and regenerative repair capacity via a simple implantation procedure.

PURPOSE

To assess the safety and efficacy of using a scaffold-free tissue-engineered construct (TEC) derived from autologous synovial membrane mesenchymal stem cells (MSCs) for effective cartilage repair.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Five patients with symptomatic knee chondral lesions (1.5-3.0 cm²) on the medial femoral condyle, lateral femoral condyle, or femoral groove were included. Synovial MSCs were isolated from arthroscopic biopsy specimens and cultured to develop a TEC that matched the lesion size. The TECs were then implanted into chondral defects without fixation and assessed up to 24 months postoperatively. The primary outcome was the safety of the procedure. Secondary outcomes were self-assessed clinical scores, arthroscopy, tissue biopsy, and magnetic resonance image-based estimation of morphologic and compositional quality of the repair tissue.

RESULTS

No adverse events were recorded, and self-assessed clinical scores for pain, symptoms, activities of daily living, sports activity, and quality of life were significantly improved at 24 months after surgery. Secure defect filling was confirmed by second-look arthroscopy and magnetic resonance imaging in all cases. Histology of biopsy specimens indicated repair tissue approaching the composition and structure of hyaline cartilage.

CONCLUSION

Autologous scaffold-free TEC derived from synovial MSCs may be used for regenerative cartilage repair via a sutureless and simple implantation procedure. Registration: 000008266 (UMIN Clinical Trials Registry number).

Time-Dependent Recovery of Human Synovial Membrane Mesenchymal Stem Cell Function After High-Dose Steroid Therapy: Case Report and Laboratory Study

BACKGROUND

The use of mesenchymal stem cells from various tissue sources to repair injured tissues has been explored over the past decade in large preclinical models and is now moving into the clinic.

PURPOSE

To report the case of a patient who exhibited compromised mesenchymal stem cell (MSC) function shortly after use of high-dose steroid to treat Bell's palsy, who recovered 7 weeks after therapy.

STUDY DESIGN

Case report and controlled laboratory study.

METHODS

A patient enrolled in a first-in-human clinical trial for autologous implantation of a scaffold-free tissue engineered construct (TEC) derived from synovial MSCs for chondral lesion repair had a week of high-dose steroid therapy for Bell's palsy. Synovial tissue was harvested for MSC preparation after a 3-week recovery period and again at 7 weeks after therapy.

RESULTS

The MSC proliferation rates and cell surface marker expression profiles from the 3-week sample met conditions for further processing. However, the cells failed to generate a functional TEC. In contrast, MSCs harvested at 7 weeks after steroid therapy were functional in this regard. Further in vitro studies with MSCs and steroids indicated that the effect of in vivo steroids was likely a direct effect of the drug on the MSCs.

CONCLUSION

This case suggests that MSCs are transiently compromised after high-dose steroid therapy and that careful consideration regarding timing of MSC harvest is critical.

CLINICAL RELEVANCE

The drug profiles of MSC donors and recipients must be carefully monitored to optimize opportunities to successfully repair damaged tissues.

Scaffold-free tissue engineering for injured joint surface restoration

Articular cartilage does not heal spontaneously due to its limited healing capacity, and thus effective treatments for cartilage injuries has remained challenging. Since the first report by Brittberg et al. in 1994, autologous chondrocyte implantation (ACI) has been introduced into the clinic. Recently, as an alternative for chondrocyte-based therapy, mesenchymal stem cell (MSC)-based therapy has received considerable research attention because of the relative ease in handling for tissue harvest, and subsequent cell expansion and differentiation. In this review, we discuss the latest developments regarding stem cell-based therapies for cartilage repair, with special focus on recent scaffold-free approaches.

Meniscal repair and regeneration: Current strategies and future perspectives

The management of meniscal injuries remains difficult and challenging. Although several clinical options exist for the treatment of such injuries, complete regeneration of the damaged meniscus has proved difficult due to the limited healing capacity of the tissue. With the advancements in tissue engineering and cell-based technologies, new therapeutic options for patients with currently incurable meniscal lesions now potentially exist. This review will discuss basic anatomy, current repair techniques and treatment options for loss of meniscal integrity. Specifically, we focus on the possibility and feasibility of the latest tissue engineering approaches, including 3D printing technologies. Therefore, this discussion will facilitate a better understanding of the latest trends in meniscal repair and regeneration, and contribute to the future application of such clinical therapies for patients with meniscal injuries.

Novel flat and wide meniscal repair material improves the ultimate load of knot breakage in a porcine trans-capsular meniscal repair model

Background

In the meniscal repair procedures, a high ultimate load capacity and low cyclic creep at the repair site are favorable and lead to good biological incorporation of the tear site after surgery. Previous biomechanical tensile tests of the meniscal sutures have identified the suture knot as the weakest point. We hypothesized that the strength of a suture knot depends on the suture shape, and therefore, we compared three differently shaped suture materials composed of the same material and quantity per length. The purpose of this study was to determine whether a novel flat and wide repair material (FWRM), which consists of braided multi-threads that are cross-sectionally flat and wide, improves the ultimate load of knot breakage in a biomechanical experiment using a porcine trans-capsular meniscal repair model.

Methods

Eighteen fresh-frozen porcine knees (n = 6 in each group) were used. A longitudinal tear in the middle segment of the medial meniscus was created and repaired with a trans-capsular inside-out method using the following suture materials: No. 2–0 braided polyester conventional suture, hollow suture, and FWRM. After the separation of the inner segment of the meniscus with leaving, the suture stability of the repaired menisci was biomechanically analyzed with a video camera system for widening after a cyclic load between 5 and 20 N was applied 300 times. Ultimate failure load and stiffness at 5 mm/ min were also analyzed.

Results

We found no significant difference in suture widening after cyclic load tests [conventional suture, mean 0.51 mm (S.D. 0.39 mm); hollow suture, mean 0.23 mm (S.D. 0.11 mm); and FWRM, mean 0.54 mm (S.D. 0.08 mm)]. The failure mode in all specimens was knot breakage. Compared with those of the other groups, the ultimate failure load of FWRM was statistically significantly higher in the load-to-failure tests (conventional suture, mean 58.8 N [S.D. 8.25 N]; hollow suture, mean 79.4 N [S.D. 10.2 N]; and FWRM, mean 97.4 N [S.D. 3.65 N]; p < 0.05).

Conclusion

FWRM improves the ultimate load of knot breakage without altering stability. This material may contribute to safe and stable meniscus repair.

Temporal mapping of photochemical reactions and molecular excited states with carbon specificity

Photochemical reactions are essential to a large number of important industrial and biological processes. A method for monitoring photochemical reaction kinetics and the dynamics of molecular excitations with spatial resolution within the active molecule would allow a rigorous exploration of the pathway and mechanism of photophysical and photochemical processes. Here we demonstrate that laser-excited muon pump-probe spin spectroscopy (photo-μSR) can temporally and spatially map these processes with a spatial resolution at the single-carbon level in a molecule with a pentacene backbone. The observed time-dependent light-induced changes of an avoided level crossing resonance demonstrate that the photochemical reactivity of a specific carbon atom is modified as a result of the presence of the excited state wavefunction. This demonstrates the sensitivity and potential of this technique in probing molecular excitations and photochemistry.

Comparison of 2 Different Formulations of Artificial Bone for a Hybrid Implant With a Tissue-Engineered Construct Derived From Synovial Mesenchymal Stem Cells: A Study Using a Rabbit Osteochondral Defect Model

BACKGROUND

Previously, we developed a hybrid implant composed of hydroxyapatite (HA)-based artificial bone coupled with a mesenchymal stem cell (MSC)-based scaffold-free tissue-engineered construct (TEC) and demonstrated its feasibility for osteochondral repair. Beta-tricalcium phosphate (βTCP) may be a promising alternative to HA, as it is a highly biocompatible material and is resorbed more rapidly than HA in vivo.

HYPOTHESIS

A βTCP-based hybrid TEC implant will exhibit superior osteochondral repair when directly compared with an HA-based hybrid implant, as tested using a rabbit osteochondral defect model.

STUDY DESIGN

Controlled laboratory study.

METHODS

Osteochondral defects were created in the femoral groove of skeletally mature rabbits. The TEC and artificial bone, using either HA or βTCP with the same porosities and similar mechanical properties, were hybridized and then implanted in the defects. A histological evaluation and microindentation testing were performed for the assessment of repair tissue.

RESULTS

Osteochondral defects treated with the TEC/βTCP implants showed more rapid subchondral bone repair at 1 month, but the cartilaginous tissue deteriorated over time out to 6 months after implantation. Osteochondral defects treated with the TEC/HA implants maintained good histological quality out to 6 months after implantation and also exhibited better biomechanical properties at 6 months as compared with the TEC/βTCP implants.

CONCLUSION

Contrary to our hypothesis, the TEC/HA hybrid implant facilitated better osteochondral repair than did the TEC/βTCP implant. The results of the present study suggest the importance of a stable restoration of subchondral bone for long-term effective osteochondral repair rather than rapid remodeling of subchondral bone.

CLINICAL RELEVANCE

This study contributes to the future selection of suitable materials for patients with osteochondral lesions.

Region-Specific Effect of the Decellularized Meniscus Extracellular Matrix on Mesenchymal Stem Cell-Based Meniscus Tissue Engineering

BACKGROUND

The meniscus is the most commonly injured knee structure, and surgical repair is often ineffective. Tissue engineering-based repair or regeneration may provide a needed solution. Decellularized, tissue-derived extracellular matrices (ECMs) have received attention for their potential use as tissue-engineered scaffolds. In considering meniscus-derived ECMs (mECMs) for meniscus tissue engineering, it is noteworthy that the inner and outer regions of the meniscus have different structural and biochemical features, potentially directing the differentiation of cells toward region-specific phenotypes.

PURPOSE

To investigate the applicability of mECMs for meniscus tissue engineering by specifically comparing region-dependent effects of mECMs on 3-dimensional constructs seeded with human bone marrow mesenchymal stem cells (hBMSCs).

STUDY DESIGN

Controlled laboratory study.

METHODS

Bovine menisci were divided into inner and outer halves and were minced, treated with Triton X-100 and DNase, and extracted with urea. Then, hBMSCs (1 × 10⁶ cells/mL) were encapsulated in a photo-cross-linked 10% polyethylene glycol diacrylate scaffold containing mECMs (60 μg/mL) derived from either the inner or outer meniscus, with an ECM-free scaffold as a control. The cell-seeded constructs were cultured with chondrogenic medium containing recombinant human transforming growth factor β3 (TGF-β3) and were analyzed for expression of meniscus-associated genes as well as for the collagen (hydroxyproline) and glycosaminoglycan content as a function of time.

RESULTS

Decellularization was verified by the absence of 4',6-diamidino-2-phenylindole (DAPI)-stained cell nuclei and a reduction in the DNA content. Quantitative real-time polymerase chain reaction showed that collagen type I expression was significantly higher in the outer mECM group than in the other groups, while collagen type II and aggrecan expression was highest in the inner mECM group. The collagen (hydroxyproline) content was highest in the outer mECM group, while the glycosaminoglycan content was higher in both the inner and outer mECM groups compared with the control group.

CONCLUSION

These results showed that the inner mECM enhances the fibrocartilaginous differentiation of hBMSCs, while the outer mECM promotes a more fibroblastic phenotype. Our findings support the feasibility of fabricating bioactive scaffolds using region-specific mECM preparations for meniscus tissue engineering.

CLINICAL RELEVANCE

This is the first report to demonstrate the feasibility of applying region-specific mECMs for the engineering of meniscus implants capable of reproducing the biphasic, anatomic, and biochemical characteristics of the meniscus, features that should contribute to the feasibility of their clinical application.