Cross-Validation of a Screening Tool to Distinguish Between Fallers and Nonfallers in Community-Dwelling Older Adults With Knee Osteoarthritis.

OBJECTIVES: This study aimed to cross-validate a previously developed knee osteoarthritis falls (KOAF) screening tool to distinguish between fallers and nonfallers among community-dwelling older adults with knee osteoarthritis (OA). DESIGN: Cross-sectional survey study. SETTING: Three independent orthopedic clinics. PARTICIPANTS: Older outpatients with knee OA (N=86; 71 women, 15 men; mean age, 75.2±6.2y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The primary outcome was to identify fallers and nonfallers among outpatients with OA based on their history of falls within the past year. We investigated factors including sex, age, body mass index, Kellgren-Lawrence grade, affected side (bilateral or unilateral knee OA), number of comorbidities, pharmacotherapy, physical therapy, pain, and activity as individual predictors of falls. Participants performed the one-leg standing test and the 5 times sit-to-stand test to determine motor function. Sensitivity, specificity, likelihood ratio, and post-test probability of the KOAF screening tool were calculated using receiver operating characteristic (ROC) curve analysis. RESULTS: The results of the one-leg standing test and 5 times sit-to-stand test differed significantly between the 2 groups (P<.05). ROC curve analysis showed that the area under the curve was 0.88 (95% confidence interval, 0.80-0.96; P<.001). The post-test probability of falls was 83.3% (positive likelihood ratio, 11.54) when the total score of KOAF screening tool was 2 points and 2.6% (negative likelihood ratio, 0.06) when the total score of KOAF screening tool was less than 1 point. CONCLUSIONS: Cross-validation results for the KOAF screening tool were better, confirming that the screening tool could distinguish between fallers and nonfallers with high accuracy. Our findings suggest that this simple screening tool could be readily used in clinical practice and could aid in clinical decision-making through providing choices for physical therapy evaluation and recommendations for physical therapy programs.

The extracellular domain of teneurin-4 promotes cell adhesion for oligodendrocyte differentiation.

Cell adhesion between oligodendrocytes and neuronal axons is a critical step for myelination that enables the rapid propagation of action potential in the central nervous system. Here, we show that the transmembrane protein teneurin-4 plays a role in the cell adhesion required for the differentiation of oligodendrocytes. We found that teneurin-4 formed molecular complexes with all of the four teneurin family members and promoted cell-cell adhesion. Oligodendrocyte lineage cells attached to the recombinant extracellular domain of all the teneurins and formed well-branched cell processes. In an axon-mimicking nanofibers assay, nanofibers coated with the recombinant teneurin-4 extracellular domain increased the differentiation of oligodendrocytes. Our results show that teneurin-4 binds to all teneurins through their extracellular domain, which facilitates the oligodendrocyte-axon adhesion, and promotes oligodendrocyte differentiation via its homophilic interaction.

Heterogeneity of Oligodendrocytes and Their Precursor Cells.

While oligodendrocytes have been thought to be homogenous, a number of reports have indicated evidences of the heterogeneity of oligodendrocytes and their precursor cells, OPCs. Almost a century ago, Del Río Hortega found three and four types of oligodendrocytes with regions where they exist and their morphologies, respectively. Interfascicular oligodendrocytes are one of the three regional dependent types and are the most typical oligodendendroglial cells that myelinate axonal fibers in the white matter tracts. In the other two, perineuronal oligodendrocyes function as reserve cells for remyelination and regulate neuronal excitability, whereas perivascular oligodendrocytes may play a role in metabolic support of axons. Among the four morphological categories, type I and II oligodendrocytes form many myelin sheaths on small-diameter axons and specific signal is required for the myelination of small-diameter axons. Type III and IV oligodendrocytes myelinate a few number of axons/or one axon, whose diameters are large. A recent comprehensive gene expression analysis with single-cell RNA sequencing identifies six different populations in mature oligodendrocytes and only one population in OPCs. However, OPCs are not uniformed developmentally and regionally. Further, the capacity of OPC differentiation depends on the environments and conditions of the tissues. Taken together, oligodendrocytes and OPCs are diverse as the other cell types in the CNS. The orchestration of these cells with their specialized functions is critical for proper functioning of the CNS.

Muscle Satellite Cell Protein Teneurin-4 Regulates Differentiation During Muscle Regeneration.

Satellite cells are maintained in an undifferentiated quiescent state, but during muscle regeneration they acquire an activated stage, and initiate to proliferate and differentiate as myoblasts. The transmembrane protein teneurin-4 (Ten-4) is specifically expressed in the quiescent satellite cells; however, its cellular and molecular functions remain unknown. We therefore aimed to elucidate the function of Ten-4 in muscle satellite cells. In the tibialis anterior (TA) muscle of Ten-4-deficient mice, the number and the size of myofibers, as well as the population of satellite cells, were reduced with/without induction of muscle regeneration. Furthermore, we found an accelerated activation of satellite cells in the regenerated Ten-4-deficient TA muscle. The cell culture analysis using primary satellite cells showed that Ten-4 suppressed the progression of myogenic differentiation. Together, our findings revealed that Ten-4 functions as a crucial player in maintaining the quiescence of muscle satellite cells.

Identification of peptides derived from the C-terminal domain of fibulin-7 active for endothelial cell adhesion and tube formation disruption.

Despite the research done on pathological angiogenesis, there is still a need for the development of new therapies against angiogenesis-related diseases. Fibulin-7 (Fbln7) is a member of the extracellular matrix fibulin protein family. The Fbln7 C-terminal fragment, Fbln7-C, binds to endothelial cells and inhibits their tube formation in culture. In this study, we screened 12 synthetic peptides, covering the fibulin-globular domain of Fbln7-C, to identify active sites for endothelial cell adhesion and in vitro antiangiogenic activity. Three peptides, fc10, fc11, and fc12, promoted Human Umbilical Vein Endothelial Cells (HUVECs) adhesion, and the morphology of HUVECs on fc10 was similar to that on Fbln7-C. EDTA and the anti-integrin ß1 function-blocking antibody inhibited HUVECs adhesion to both fc10 and fc12, and heparin inhibited HUVECs adhesion to both fc11 and fc12. fc10 and fc11 inhibited HUVECs tube formation. Our results suggest that three peptides from Fbln7-C are biologically active for endothelial cell adhesion and disrupt the tube formation, suggesting a potential therapeutic use of these peptides for angiogenesis-related diseases. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 184-195, 2016.

Teneurin-4 promotes cellular protrusion formation and neurite outgrowth through focal adhesion kinase signaling.

Teneurin-4 (Ten-4), a transmembrane protein, is highly expressed in the central nervous system; however, its cellular and molecular function in neuronal differentiation remains unknown. In this study, we aimed to elucidate the function of Ten-4 in neurite outgrowth. Ten-4 expression was induced during neurite outgrowth of the neuroblastoma cell line Neuro-2a. Ten-4 protein was localized at the neurite growth cones. Knockdown of Ten-4 expression in Neuro-2a cells decreased the formation of the filopodia-like protrusions and the length of individual neurites. Conversely, overexpression of Ten-4 promoted filopodia-like protrusion formation. In addition, knockdown and overexpression of Ten-4 reduced and elevated the activation of focal adhesion kinase (FAK) and Rho-family small GTPases, Cdc42 and Rac1, key molecules for the membranous protrusion formation downstream of FAK, respectively. Inhibition of the activation of FAK and neural Wiskott-Aldrich syndrome protein (N-WASP), which is a downstream regulator of FAK and Cdc42, blocked protrusion formation by Ten-4 overexpression. Further, Ten-4 colocalized with phosphorylated FAK in the filopodia-like protrusion regions. Together, our findings show that Ten-4 is a novel positive regulator of cellular protrusion formation and neurite outgrowth through the FAK signaling pathway.

A C-terminal fragment of fibulin-7 interacts with endothelial cells and inhibits their tube formation in culture.

We have previously demonstrated that fibulin-7 (Fbln7) is expressed in teeth by pre-odontoblast and odontoblast cells, localized in the basement membrane and dentin matrices, and is an adhesion molecule for dental mesenchyme cells and odontoblasts. Fbln7 is also expressed in blood vessels by endothelial cells. In this report, we show that a recombinant C-terminal Fbln7 fragment (Fbln7-C) bound to Human Umbilical Vein Endothelial Cells (HUVECs) but did not promote cell spreading and actin stress fiber formation. Fbln7-C binding to HUVECs induced integrin clustering at cell adhesion sites with other focal adhesion molecules, and sustained activation of FAK, p130Cas, and Rac1. In addition, RhoA activation was inhibited, thereby preventing HUVEC spreading. As endothelial cell spreading is an important step for angiogenesis, we examined the effect of Fbln7-C on angiogenesis using in vitro assays for endothelial cell tube formation and vessel sprouting from aortic rings. We found that Fbln7-C inhibited the HUVEC tube formation and the vessel sprouting in aortic ring assays. Our findings suggest potential anti-angiogenic activity of the Fbln7 C-terminal region.

Abnormal neural crest innervation in Sox10-Venus mice with all-trans retinoic acid-induced anorectal malformations.

BACKGROUND/PURPOSE: Despite technical advances in the surgical/medical care of anorectal malformation (ARM), persistent unsatisfactory postoperative bowel habit has been attributed to histopathologic abnormalities of the distal rectum/pouch (DRP) and hypoplasia of anal sphincter muscles (ASM). We used Sox10-Venus mice with ARM induced by all-trans retinoic acid (ATRA) to investigate neural crest cell (NCC) innervation in the DRP and ASM. METHOD: Pregnant Sox10-Venus mice were administered single doses of 50, 70, or 100 mg/kg of ATRA on embryonic day 8.5 (E8.5) then sacrificed on either E16.5 or E19.5. Bowel specimens comprising the anorectum were examined using fluorescence microscopy without immunohistochemical staining (FMIS). Anti-PGP9.5 was used to delineate ganglion cells and anti-SMA for smooth muscles. RESULTS: The appropriate dose of ATRA for inducing ARM was 50 mg/kg. Under FMIS, all ARM embryos (n = 5; all high type; 3 male:2 female) had less NCC innervation with thick Venus-positive nerve fibers in the DRP compared with normal embryos (n = 8); there was abnormal NCC innervation in the DRP and absent ASM in ARM mice. CONCLUSION: We are the first to delineate abnormal enteric nervous system innervation in the DRP of ARM mice without using immunohistochemical staining techniques thus allowing specimens to be examined without any distortion.

Teneurin-4 is a novel regulator of oligodendrocyte differentiation and myelination of small-diameter axons in the CNS.

Myelination is essential for proper functioning of the CNS. In this study, we have identified a mouse mutation, designated furue, which causes tremors and hypomyelination in the CNS, particularly in the spinal cord, but not in the sciatic nerve of the PNS. In the spinal cord of the furue mice, myelination of small-diameter axons was dramatically reduced, and differentiation of oligodendrocytes, the myelin-forming cells in the CNS, was inhibited. We subsequently found that the furue mutation was associated with a transgene insertion into the teneurin-4 (Ten-4, Ten-m4/Odz4) gene, encoding a transmembrane protein of unknown function. Ten-4 was strongly expressed in the spinal cord of wild-type mice and was induced during normal oligodendrocyte differentiation. In contrast, in the furue mice, the expression of Ten-4 was absent. Differentiation and cellular process formation of oligodendrocytes were inhibited in primary cell culture from the furue mice. Cell differentiation and process formation were also inhibited in the oligodendrocyte progenitor cell line CG-4 after suppression of Ten-4 expression by shRNA. Furthermore, Ten-4 positively regulated focal adhesion kinase, an essential signaling molecule for oligodendrocyte process formation and myelination of small-diameter axons. These findings suggest that Ten-4 is a novel regulator of oligodendrocyte differentiation and that it plays a critical role in the myelination of small-diameter axons in the CNS.

Validity of submaximal exercise testing in adults with athetospastic cerebral palsy.

OBJECTIVE: To examine the validity of the multistage submaximal cycle ergometer test for adults with athetospastic cerebral palsy. DESIGN: Cross-sectional and correlative study. Oxygen uptake and heart rates were recorded while the participants underwent the maximal cycle ergometer test and the multistage submaximal cycle ergometer test. Peak oxygen consumption (Vo(2)peak) was achieved by the maximal cycle test. Maximum oxygen consumption (VO(2)max) was predicted by the multistage submaximal cycle ergometer test. SETTING: Research laboratory setting. PARTICIPANTS: Adults with athetospastic cerebral palsy (N=16; 10 women and 6 men; mean age ± SD, 43.7±14.5y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Peak VO(2) was compared with the predicted VO(2)max. RESULTS: Mean VO(2)peak and the predicted VO(2)max ± SD were 866.9±202.9 mL/min(-1) and 857.4±248.4 mL/min(-1), respectively. There was not a significant difference between VO(2)peak values and the predicted VO(2)max values (r=.28). And there was a significant correlation between VO(2)peak values and the predicted VO(2)max values (r=.94, P<.001). SE of the estimate (or SE for X to Y) was 71.2 mL/min(-1), equivalent to 7.4%. CONCLUSIONS: The multistage submaximal cycle ergometer test may provide a valid VO(2)max estimate of adults with athetospastic cerebral palsy.

The molecular regulation of oligodendrocyte development and CNS myelination by ECM proteins.

Oligodendrocytes are myelin-forming cells in the central nervous system (CNS). The development of oligodendrocytes is regulated by a large number of molecules, including extracellular matrix (ECM) proteins that are relatively less characterized. Here, we review the molecular functions of the major ECM proteins in oligodendrocyte development and pathology. Among the ECM proteins, laminins are positive regulators in oligodendrocyte survival, differentiation, and/or myelination in the CNS. Conversely, fibronectin, tenascin-C, hyaluronan, and chondroitin sulfate proteoglycans suppress the differentiation and myelination. Tenascin-R shows either positive or negative functions in these activities. In addition, the extracellular domain of the transmembrane protein teneurin-4, which possesses the sequence homology with tenascins, promotes the differentiation of oligodendrocytes. The activities of these ECM proteins are exerted through binding to the cellular receptors and co-receptors, such as integrins and growth factor receptors, which induces the signaling to form the elaborated and functional structure of myelin. Further, the ECM proteins dynamically change their structures and functions at the pathological conditions as multiple sclerosis. The ECM proteins are a critical player to serve as a component of the microenvironment for oligodendrocytes in their development and pathology.

Calf circumference positively correlates with calf muscle thickness and negatively correlates with calf subcutaneous fat thickness and percent body fat in non-obese healthy young adults.

BACKGROUND: Calf circumference is measured for assessing sarcopenia, nutrition status, percent body fat or obesity. However, there has been no study that investigated the relationship between calf circumference and calf subcutaneous fat tissue thickness. Therefore, the aim of this study was to investigate the relationship between calf circumference, calf muscle thickness, and calf subcutaneous fat tissue thickness in non-obese healthy young adults. METHODS: The study participants were non-obese 22 women (20.1±0.8 years) and 21 men (20.0±0.8 years). The right calf circumference was measured in prone position at the point where the circumference was maximal by visual recognition using a measuring tape. Then, thickness of calf subcutaneous fat tissue and calf muscles were measured with an ultrasonic diagnostic equipment. RESULTS: There was a positive relationship between calf circumference and calf muscle thickness both in women (r=0.58, P<0.01) and men (r=0.46, P<0.05), negative relationship between calf circumference and calf subcutaneous fat tissue thickness both in women (r=-0.43, P<0.05) and men (r=-0.67, P<0.001), no correlation between calf circumference and percent body fat both in women (r=0.04, P=0.87) and men (r=0.41, P=0.06), and a negative relationship between calf subcutaneous fat tissue thickness and percent body fat both in women (r=-0.48, P<0.05) and men (r=-0.46, P<0.05). CONCLUSIONS: The present study showed that a larger calf indicated larger calf muscle thickness, and largely different from previous studies, a lower calf subcutaneous fat tissue thickness. That is because when the calf circumference increases, calf subcutaneous fat tissue thickness should be thinner to keep the percent body fat equal in non-obese healthy young adults. The finding will help to get a better understanding of the nature of the calf.

Development of type I/II oligodendrocytes regulated by teneurin-4 in the murine spinal cord.

In the spinal cord, the axonal tracts with various caliber sizes are myelinated by oligodendrocytes and function as high-velocity ways for motor and sensory nerve signals. In some neurological disorders, such as multiple sclerosis, demyelination of small caliber axons is observed in the spinal cord. While type I/II oligodendrocytes among the four types are known to myelinate small diameter axons, their characteristics including identification of regulating molecules have not been understood yet. Here, we first found that in the wild-type mouse spinal cord, type I/II oligodendrocytes, positive for carbonic anhydrase II (CAII), were located in the corticospinal tract, fasciculus gracilis, and the inside part of ventral funiculus, in which small diameter axons existed. The type I/II oligodendrocytes started to appear between postnatal day (P) 7 and 11. We further analyzed the type I/II oligodendrocytes in the mutant mice, whose small diameter axons were hypomyelinated due to the deficiency of teneurin-4. In the teneurin-4 deficient mice, type I/II oligodendrocytes were significantly reduced, and the onset of the defect was at P11. Our results suggest that CAII-positive type I/II oligodendrocytes myelinate small caliber axons in the spinal cord and teneurin-4 is the responsible molecule for the generation of type I/II oligodendrocytes.

Chain-specific heparin-binding sequences in the laminin alpha chain LG45 modules.

Laminin alpha chains contain five tandem globular modules (LG1-5) at the C-terminus. Here, we focused on the LG45 module, which play a critical biological role via binding to heparin/heparan sulfate, and examined their chain-specific heparin-binding affinity. The relative heparin-binding affinity of recombinant laminin alpha chain LG45 proteins was as follows: alpha5 > alpha4 > alpha1 > alpha2 and alpha3. The alpha5 chain LG45 module also promoted the strongest cell attachment. We screened heparin-binding sequences using the recombinant alpha5LG45 protein and 43 synthetic peptides. Four peptides, A5G71 (GPLPSYLQFVGI) (IC(50) = 91.8 microM), A5G77 (LVLFLNHGHFVA) (IC(50) = 7.0 microM), A5G81 (AGQWHRVSVRWG) (IC(50) = 5.9 microM), and A5G94 (KMPYVSLELEMR) (IC(50) = 0.84 microM), inhibited the heparin-binding of rec-alpha5LG45. Additionally, the same four peptides exhibited dose-dependent heparin-binding activity in a solid-phase assay. We found that the alpha5 chain LG45 module contains four heparin-binding sequences, and this number is higher than that of the other LG45 modules (alpha2 and alpha3, one sequence; alpha1 and alpha4, two sequences). The data suggest that the active sequences identified from the synthetic peptide screening contribute to the heparin-binding activity of the LG45 module. Most of the heparin-binding sequences in the LG45 modules are located in the N-terminal regions of the LG4 module within the loop regions in the proteins. The data suggest that the N-terminal loop regions of the LG4 module are mainly involved in the heparin/heparan sulfate-mediated biological functions.

Derivation of a clinical prediction rule to determine fall risk in community-dwelling individuals with knee osteoarthritis: a cross-sectional study.

We derived a clinical prediction rule (CPR) to determine fall risk. The probability of falls increased, with positive likelihood ratio being 17.8 and post-test probability (positive predictive value) being 88.2%, in cases where the CPR score was 2 points. Our CPR could be a useful screening test to detect fall risk probability. PURPOSE: We aimed to examine the risk factors for falls in individuals with knee osteoarthritis (OA) and derive a clinical prediction rule (CPR) to determine fall risk. METHODS: Eighty-one individuals with medial compartment knee OA were included. The outcome was whether the participants had a self-reported fall within the past 1 year of this study being conducted. The collected data included sex, age, body mass index, Kellgren-Lawrence grade, lesion type (bilateral or unilateral knee OA), pain (rated using the visual analog scale), muscle strength test of the quadriceps femoris, one-leg standing test (OLST), five times sit-to-stand test (FTSST), and 5-m walk test, which were used in binomial logistic regression analysis. The outcome measure of the analysis was whether the study participants belonged to a fall or non-fall group. Receiver operating characteristic (ROC) analysis was performed for the outcome measurements, and the factors were selected by binomial logistic regression analysis. Then, a CPR to determine fall risk was extracted, and its diagnostic characteristics were calculated. RESULTS: Binomial logistic regression analysis showed that the OLST and FTSST were significant. ROC analysis showed that the cut-off values of the OLST and FTSST were 5.3 s and 7.9 s, respectively. The post-test probability (positive predictive value) increased to 88.2% (positive likelihood ratio = 17.8) when the OLST and FTSST were both positive (the CPR score was 2 points). CONCLUSION: The CPR obtained from this study would be useful as a screening test to detect the fall risk probability in individuals with knee OA.

Laminin α2, α4, and α5 Chains Positively Regulate Migration and Survival of Oligodendrocyte Precursor Cells.

In the developing central nervous system (CNS), oligodendrocyte precursor cells (OPCs) migrate along blood vessels and are widely distributed in the CNS. Meanwhile, OPCs require survival factors from the extracellular microenvironment. In other tissues, laminins, heterotrimetric (αßγ) extracellular matrix proteins, promote cell migration and survival. However, the expression pattern and functions of laminins in OPC development remain poorly understood. In the present study, we first investigated the expression of laminin α chains, which bind to cell surface receptors such as integrins, in the postnatal murine brain. We found that laminin α1, α2, α4, and α5 chains were expressed around blood vessels and OPCs attached the laminin α chain-positive vessels. We then evaluated the effect of these laminins on OPCs activity using recombinant laminin E8s (LME8s) that are minimally active fragments of the laminin isoforms. OPCs attached on LM211E8, LM411E8, and LM511E8, containing laminin α2, α4, and α5 chains, respectively, through integrin ß1. Further, these three LME8s promoted migration of OPCs, and OPC survival was prolonged on either LM411E8 or LM511E8 via the activation of focal adhesion kinase. Together, our findings suggest that laminins expressed surrounding blood vessels positively regulate migration and survival of OPCs through the integrin ß1-FAK pathway.

Minimal Detectable Change for Motor Function Tests in Patients with Knee Osteoarthritis.

OBJECTIVE: Improvement in a subject's motor function is clinically evaluated by comparing measurements of the motor function tests taken before and after an intervention. Consequently, it is important to increase the accuracy of the determination of the intervention effect by confirming the minimal detectable change (MDC), which is an index representing the limits of measurement errors in motor function tests. This study aimed to examine the MDC of the five-time sit-to-stand test (FTSST) and the 5-m walk test (5mWT) in patients with knee osteoarthritis (OA). METHODS: In this cross-sectional study, 83 patients (63 women and 20 men, mean age: 73.7±8.0 years) with knee OA were subjected to two trials of the FTSST and 5mWT. The maximum walking speed was calculated using the walking time in the 5mWT, and the intraclass correlation coefficients (ICCs) were determined. RESULTS: The ICCs (1,1) of the FTSST, the walking time in the 5mWT, and the walking speed were 0.90, 0.83, and 0.81, respectively. The MDC95 for the FTSST time, walking time in the 5mWT, and walking speed were 1.71 s, 0.99 s, and 0.36 m/s, respectively. CONCLUSION: If the observed changes in the motor function tests exceed 1.71 s for FTSST time, 0.99 s for walking time in the 5mWT, or 0.36 m/s for walking speed, then an improvement in function is indicated. Such an improvement would reflect the effectiveness of the intervention. These findings may aid in clinical decision making when using motor function tests in patients with knee OA.

Recapitulation of Extracellular LAMININ Environment Maintains Stemness of Satellite Cells In Vitro.

Satellite cells function as precursor cells in mature skeletal muscle homeostasis and regeneration. In healthy tissue, these cells are maintained in a state of quiescence by a microenvironment formed by myofibers and basement membrane in which LAMININs (LMs) form a major component. In the present study, we evaluated the satellite cell microenvironment in vivo and found that these cells are encapsulated by LMα2-5. We sought to recapitulate this satellite cell niche in vitro by culturing satellite cells in the presence of recombinant LM-E8 fragments. We show that treatment with LM-E8 promotes proliferation of satellite cells in an undifferentiated state, through reduced phosphorylation of JNK and p38. On transplantation into injured muscle tissue, satellite cells cultured with LM-E8 promoted the regeneration of skeletal muscle. These findings represent an efficient method of culturing satellite cells for use in transplantation through the recapitulation of the satellite cell niche using recombinant LM-E8 fragments.

Anterior cruciate ligament-derived mesenchymal stromal cells have a propensity to differentiate into the ligament lineage.

INTRODUCTION: The anterior cruciate ligament (ACL) consists of various components, such as collagen, elastin fibres, and fibroblasts. Because ACL has a poor regenerative ability, ACL reconstruction need require the use of autologous tendons. In recent years, tissue-resident stem cells have been studied to promote ACL regeneration as an alternatively method. However, the existence of stem cells in ligaments has not been clearly defined. Here, we prospectively isolated stem cells from ACLs and characterized their properties. METHODS: ACLs from 11 donors and bone marrows (BM) from 8 donors were obtained with total knee arthroplasty. We used flow cytometry to screen the cell surface markers on ACL cells. Frozen sections were prepared from patient ACL tissues and stained with specific antibodies. Cultured ACL-derived and BM-derived cells at passage 3 were differentiated into adipocytes, osteoblasts and tendon/ligament cells. RESULTS: ACL-derived mesenchymal stem/stromal cells (ACL-MSCs) expressed high levels of CD73 and CD90. Immunohistochemical analyses revealed that ACL-MSCs were located on the inner surface of ACL sinusoids. Furthermore, the expression of cell surface antigens was clearly different between ACL-MSCs and bone marrow (BM)-derived MSCs (BM-MSCs) at the time of isolation, but the two cell populations became indistinguishable after long-term culture. Interestingly, ACL-MSCs are markedly different from BM-MSCs in their differentiation ability and have a high propensity to differentiate into ligament-committed cells. CONCLUSIONS: Our findings suggest that ACL-MSCs express CD90 and CD73 markers, and their differentiation capacity is maintained even through culture. The cell population having tissue-specific properties is an important research target for investigating the ligament therapies.

Training effects of wheelchair dance on aerobic fitness in bedridden individuals with severe athetospastic cerebral palsy rated to GMFCS level V.

BACKGROUND: There were few studies about training effects of wheelchair dance on aerobic fitness in the bedridden individuals with severe cerebral palsy for whom the traditional maximal or submaximal exercise tests were not applicable. As the oxygen pulse (O2P), the oxygen uptake divided by the heart rate, is regarded to be a relative measure of stroke volume and the O2P correlates to peak oxygen uptake, we would be able to assess the training effects of wheelchair dance on aerobic fitness in those individuals measuring O2P. AIM: To study training effects of wheelchair dance on aerobic fitness in bedridden individuals with severe athetospastic cerebral palsy. DESIGN: Pre-post study design. SETTING: A laboratory and a community care center. POPULATION: Bedridden individuals with athetospastic cerebral palsy rated to Gross Motor Function Classification System (GMFCS) level V (N.=6). METHODS: The O2P was compared between during the rest, the waltz, and the jive at the baseline, the 3rd, the 6th, and the 12th month of the intervention of wheelchair dance 6 to 15 minutes at a time, 2 days a week or more. RESULTS: Paired Student's t-test showed that O2P during the waltz and the jive was significantly increased compared with that during the rest at the 6th and the 12th month, and O2P during the jive was also significantly increased compared with that during the rest at the 3rd, the 6th, and the 12th month of the intervention period. CONCLUSIONS AND CLINICAL REHABILITATION IMPACT: This is the first study that shows wheelchair dance may possibly increase aerobic fitness in bedridden individuals with severe athetospastic cerebral palsy rated GMFCS level V. Future studies with a larger sample will be warranted to prove the claim.