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Background It is still controversial whether which femoral tunnel creation technique is best during anterior cruciate ligament reconstruction (ACLR). We aimed to clarify the features of three different techniques based on the femoral tunnel position created with the same tunnel-creating concept and the measurement data. Methods The femoral tunnel of double-bundle (DB) ACLR was created using the behind-remnant approach in a remnant preserved manner following the policy of our institute. The trans-tibial approach (TT) was applied for all primary ACL injured cases until December 2012. The trans-portal approach (TP) was applied from January to September 2013, and the outside-in approach (OI) was indicated from October 2013 to March 2014. We compared the femoral tunnel aperture positions with the postoperative three-dimensional computed tomography (3D-CT). Additionally, the femoral tunnel length and the septum distance of each anteromedial (AM) and posterolateral (PL) tunnel were analyzed. Results The AM tunnel aperture position of TT was significantly higher and shallower than that of TP in knee flexion position. The femoral tunnel length of TP was significantly shorter than that of TT and OI. The septum between each tunnel of OI trended wider than that of TT and TP. Conclusions The AM tunnel aperture position of TT runs the risk of a high and shallow position. TP runs the risk of insufficiently short tunnel length. It is important to apply each method flexibly to each case because no single best approach was found.

It is thought that a few treatment-resistant cells form heterogenous recurrences and metastases, but what cells make complex tumor lineage is unexplored in colorectal cancer (CRC). To elucidate the cells that escape from treatment and form recurrences and metastases, the gene expression landscape, and drug susceptibility were explored using patient-derived organoids (PDOs). Drug sensitivities of 16 PDOs including eight PDOs derived from patients with distant metastases were evaluated. t-SNE analysis clearly showed four clusters, including two clusters based on response to therapy (good and poor). RNA sequence analysis showed that poor-response PDOs were enriched in gene sets related to distant metastasis, recurrence, and treatment resistance compared with good-response PDOs. Expression of nine genes (CBS, E2F8, GCNT1, NETO2, PLPP5, POU5F1, XRCC2, RECQL4, and ZNF681) were characteristic in the poor-response PDOs. Among them, we focused on POU5F1 gene that characterized liver metastasis in CRC from our previous report. Further analysis revealed that POU5F1-positive cells survive after anticancer drug treatment, and they were produced from POU5F1-expressing cells, not POU5F1-negative cells. Notably, isolated single POU5F1-expressing cell produced a heterogeneous population of cells expressing various differentiation markers both in vitro and in vivo. Single POU5F1-expressing cell also reconstructed ductal structure with mucus-producing ability. Cells produced from POU5F1-expressing cells were thought to construct tumor diversity remaining various differentiation stage. Single-cell RNA sequencing was performed to reveal the heterogeneous population with treatment resistance. The seven characteristic clusters were identified and the number of cells in clusters 2, 4, and 6 increased at the time of tumor re-growth after anticancer drug treatment. Cluster 2 was characterized by cell-cycle score. When cluster 4 was set as the root of the proliferative trajectory, the trajectory of cluster 4→3→6 emerged with characteristic gene expression profiles. The Wnt signaling pathway was enriched in cluster 4, suggesting stem cell characteristics. Moreover, Glycolysis, HIF-1 signaling, and ferroptosis pathways, which are also reported as properties of persister cells were enriched in cluster 6. Herein, we report the features derived from single-cell RNA seq analysis and further examinations in vitro, in vivo, and in clinical specimens. Citation Format: Shiki Fujino, Aya Ito, Masayoshi Yasui, Chu Matsuda, Masayuki Ohue, Masafumi Horie, Shinichi Yachida, Yuichiro Doki, Hidetoshi Eguchi, Norikatsu Miyoshi. Single-cell RNA sequencing of patient-derived organoid reveals treatment-induced tumor resistance through cancer stem cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 892.

The neuroendocrine carcinoma of the gastrointestinal system (GIS-NEC) is a rare but highly malignant neoplasm. We analyzed 115 cases using whole-genome/exome sequencing, transcriptome sequencing, DNA methylation assays, and/or ATAC-seq and found GIS-NECs to be genetically distinct from neuroendocrine tumors (GIS-NET) in the same location. Clear genomic differences were also evident between pancreatic NECs (Panc-NEC) and nonpancreatic GIS-NECs (Nonpanc-NEC). Panc-NECs could be classified into two subgroups (i.e., “ductal-type” and “acinar-type”) based on genomic features. Alterations in TP53 and RB1 proved common in GIS-NECs, and most Nonpanc-NECs with intact RB1 demonstrated mutually exclusive amplification of CCNE1 or MYC. Alterations of the Notch gene family were characteristic of Nonpanc-NECs. Transcription factors for neuroendocrine differentiation, especially the SOX2 gene, appeared overexpressed in most GIS-NECs due to hypermethylation of the promoter region. This first comprehensive study of genomic alterations in GIS-NECs uncovered several key biological processes underlying genesis of this very lethal form of cancer.Significance:GIS-NECs are genetically distinct from GIS-NETs. GIS-NECs arising in different organs show similar histopathologic features and share some genomic features, but considerable differences exist between Panc-NECs and Nonpanc-NECs. In addition, Panc-NECs could be classified into two subgroups (i.e., “ductal-type” and “acinar-type”) based on genomic and epigenomic features.This article is highlighted in the In This Issue feature, p. 587

Periodontitis is a chronic inflammatory disease leading to progressive connective tissue degradation and loss of the tooth-supporting bone. Clinical and experimental studies suggest that hepatocyte growth factor (HGF) is involved in the dysregulated fibroblast–epithelial cell interactions in periodontitis. The aim of this study was to explore effects of HGF to impact fibroblast-induced collagen degradation. A patient-derived experimental cell culture model of periodontitis was applied. Primary human epithelial cells and fibroblasts isolated from periodontitis-affected gingiva were co-cultured in a three-dimensional collagen gel. The effects of HGF neutralizing antibody on collagen gel degradation were tested and transcriptome analyses were performed. HGF neutralizing antibody attenuated collagen degradation and elicited expression changes of genes related to extracellular matrix (ECM) and cell adhesion, indicating that HGF signaling inhibition leads to extensive impact on cell–cell and cell–ECM interactions. Our study highlights a potential role of HGF in periodontitis. Antagonizing HGF signaling by a neutralizing antibody may represent a novel approach for periodontitis treatment. Supplementary Information The online version contains supplementary material available at 10.1007/s10266-021-00625-0.

Epithelial–mesenchymal transition (EMT) is a cellular process during which epithelial cells acquire mesenchymal phenotypes. Cancer cells undergo EMT to acquire malignant features and TGF-β is a key regulator of EMT. Here, we demonstrate for the first time that TGF-β could elicit EMT in a mouse lung adenocarcinoma cell line. TGF-β signaling activation led to cell morphological changes corresponding to EMT and enhanced the expression of mesenchymal markers and EMT-associated transcription factors in CMT64 lung cancer cells. RNA-sequencing analyses revealed that TGF-β increases expression of Tead transcription factors and an array of Tead2 target genes. TGF-β stimulation also resulted in alternative splicing of several genes including Cd44, tight junction protein 1 (Tjp1), and Cortactin (Cttn). In parallel with EMT, TGF-β enhanced cell growth of CMT64 cells and promoted tumor formation in a syngeneic transplantation model. Of clinical importance, the expression of TGF-β-induced genes identified in CMT64 cells correlated with EMT gene signatures in human lung adenocarcinoma tissue samples. Furthermore, TGF-β-induced gene enrichment was related to poor prognosis, underscoring the tumor-promoting role of TGF-β signaling in lung adenocarcinoma. Our cellular and syngeneic transplantation model would provide a simple and useful experimental tool to study the significance of TGF-β signaling and EMT.

Molecular and functional characterization of alveolar epithelial type I (AT1) cells has been challenging due to difficulty in isolating sufficient numbers of viable cells. Here we performed single-cell RNA-sequencing (scRNA-seq) of tdTomato+ cells from lungs of AT1 cell-specific Aqp5-Cre-IRES-DsRed (ACID), R26tdTomato reporter mice. Following enzymatic digestion, CD31-CD45-E-cadherin+tdTomato+ cells were subjected to fluorescence-activated cell sorting (FACS) followed by scRNA-seq. Cell identity was confirmed by immunofluorescence using cell type-specific antibodies. After quality control, 92 cells were analyzed. Most cells expressed &lsquo, conventional&rsquo, AT1 cell markers (Aqp5, Pdpn, Hopx, Ager), with heterogeneous expression within this population. The remaining cells expressed AT2, club, basal or ciliated cell markers. Integration with public datasets identified three robust AT1 cell- and lung-enriched genes, Ager, Rtkn2 and Gprc5a, that were conserved across species. GPRC5A co-localized with HOPX and was not expressed in AT2 or airway cells in mouse, rat and human lung. GPRC5A co-localized with AQP5 but not pro-SPC or CC10 in mouse lung epithelial cell cytospins. We enriched mouse AT1 cells to perform molecular phenotyping using scRNA-seq. Further characterization of putative AT1 cell-enriched genes revealed GPRC5A as a conserved AT1 cell surface marker that may be useful for AT1 cell isolation.

Background: A subgroup of lung adenocarcinoma shows neuroendocrine differentiation and expression of achaete-scute family bHLH transcription factor 1 (ASCL1). We previously demonstrated that ASCL1 exerts tumor-promoting effects by inducing a broad array of genes. MicroRNAs (miRNAs) regulate gene expression by binding to the 39UTRs of target mRNAs. Multiple miRNAs modulate a variety of cellular processes. However, miRNA profiles regulated by ASCL1 in lung adenocarcinoma cells remain unexplored. Method: We analyzed public database of gene expression profiling (RNA-sequencing and miRNA expression data). We also studied miRNA profiles in ASCL1-positive lung adenocarcinoma cells and identified a subset of miRNAs downregulated by ASCL1 knockdown. We examined functions of genes suppressed by miRNAs in ASCL1-positive lung adenocarcinoma cell line, VMRC-LCD. Result: Clinically relevant 15 genes including ZFP36L1 were identified that were suppressed by ASCL1 in lung adenocarcinoma. MiRNA array analysis were carried out to determine miRNAs regulated by ASCL1 in VMRC-LCD cells. We noted miR-124-3p which has been recently implicated with lung cancer. Interestingly, the 3’UTR region of ZFP36L1 gene contained target sequences for miR-124-3p. We further validated the effect of miR-124-3p mimics on ZFP36L1 expression. Overexpression of ZFP36L1 in VMRC-LCD cell line is associated with cell proliferation and induction of apoptosis. Conclusion: ASCL1 suppress ZFP36L1 expression by regulating miR124-3p expression in lung adenocarcinoma. It elucidated a novel regulatory network of mRNAs and miRNAs mediated by ASCL1 and related to neuroendocrine features.

TitleA mouse model of asthma­–chronic obstructive pulmonary disease overlap induced by intratracheal papain

The master regulator of neuroendocrine differentiation, achaete-scute complex homolog 1 (ASCL1) defines a subgroup of lung adenocarcinoma. However, the mechanistic role of ASCL1 in lung tumorigenesis and its relation to the immune microenvironment is principally unknown. Here, the immune landscape of ASCL1-positive lung adenocarcinomas was characterized by immunohistochemistry. Furthermore, ASCL1 was transduced in mouse lung adenocarcinoma cell lines and comparative RNA-sequencing and secretome analyses were performed. The effects of ASCL1 on tumorigenesis were explored in an orthotopic syngeneic transplantation model. ASCL1-positive lung adenocarcinomas revealed lower infiltration of CD8+, CD4+, CD20+, and FOXP3+ lymphocytes and CD163+ macrophages indicating an immune desert phenotype. Ectopic ASCL1 upregulated cyclin transcript levels, stimulated cell proliferation, and enhanced tumor growth in mice. ASCL1 suppressed secretion of chemokines, including CCL20, CXCL2, CXCL10, and CXCL16, indicating effects on immune cell trafficking. In accordance with lower lymphocytes infiltration, ASCL1-positive lung adenocarcinomas demonstrated lower abundance of CXCR3-and CCR6-expressing cells. In conclusion, ASCL1 mediates its tumor-promoting effect not only through cell-autonomous signaling but also by modulating chemokine production and immune responses. These findings suggest that ASCL1-positive tumors represent a clinically relevant lung cancer entity.

Small cell lung cancer (SCLC) is a neuroendocrine tumour that exhibits rapid growth and metastatic spread. Although SCLC represents a prototypically undifferentiated cancer type, thyroid transcription factor-1 (TTF-1, gene symbol NKX2-1), a master regulator for pulmonary epithelial cell differentiation and lung morphogenesis, is strongly upregulated in this aggressive cancer type. The aim of this study was to evaluate a functional role for TTF-1 in SCLC. We demonstrated that achaete-scute complex homolog 1 (ASCL1), an essential transcription factor for neuroendocrine differentiation, positively regulated TTF-1 in SCLC cell lines. Subsequently, we described genes and microRNAs (miRNAs) that were possibly controlled by TTF-1 and identified nuclear factor IB (NFIB), a recently characterised driver of SCLC progression, as a transcriptional target of TTF-1. Our findings shine light on a regulatory axis in SCLC consisting of ASCL1/TTF-1/NFIB that potentially contributes to the tumourigenesis of SCLC. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Objectives To compare the effects of anterior cruciate ligament (ACL) injuries and the preoperative period on functional status in different sports using preoperative patient data from the Multicenter Arthroscopic Knee Surgery (MAKS) study, a multicentre prospective cohort study of patients who underwent ACL reconstructions and meniscal surgeries conducted in 2013. Methods Of the 1648 patients registered in the MAKS study cohort, 826 underwent unilateral primary ACL reconstruction. These patients were divided into three groups based on sports activity type: contact, fighting and non-contact. The patients were further divided into two subgroups according to preoperative period data: acute (≤3 months) and chronic (>3 months). We standardised the preoperative evaluation items (Knee injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC) subjective form, and Lysholm score) and surgical records. Results The mean Lysholm score in the non-contact group was statistically significantly better than that in the fighting group. The two KOOS subcategories were statistically significantly superior in the non-contact group than in the fighting group. In the contact group, acute cases showed statistically significantly lower IKDC subjective scores and lower scores in two KOOS subcategories than the chronic cases. In the fighting group, chronic cases showed better IKDC subjective scores and scores for three KOOS subcategories than the acute cases. In the non-contact group, chronic cases showed better IKDC subjective scores and scores for all KOOS subcategories than the acute cases. Conclusion When athletes with ACL injuries are divided by sport type into fighting, contact and non-contact groups, the functional status of fighting sport athletes was more negatively influenced by ACL injury than those of non-contact sport athletes. When divided into acute and chronic phases, overall acute cases showed lower scores than the chronic cases in all sport types. In acute cases, the functional status of fighting sport athletes was more negatively influenced than non-contact sport athletes, whereas in chronic cases, there were no differences among the different sport types. The sport types and postinjury period should be considered for decision-making on therapeutic measures of patients with ACL injuries. Level of evidence Level II.

Purpose Discoid meniscus often causes mechanical problems and needs surgical treatment at an early age. However, many aspects of its morphological development and changes remain unknown. The purpose of this study was to investigate the insertion of the femoral anterior cruciate ligament (ACL) via the behind-ACL approach and the morphology of the lateral femoral condyle to which the ACL attaches to clarify the morphological characteristics of the knee with discoid lateral meniscus (DLM). Method Sixty-six patients with meniscus injury who underwent arthroscopic surgery were retrospectively reviewed. Preoperative plane radiographs were reviewed. To evaluate the shape of the femoral condyle, the ratio of the medial and lateral condyles, obliquity of the inter-epicondylar line, and the prominence ratio were assessed. From the arthroscopic observation using the behind-ACL approach, the insertion of the femoral ACL was classified as low, middle, and high based on the height from the deepest area of the articular surface to the direct insertion, including fibrous extension from the joint surface at 90° flexion. Results Twenty-nine patients had DLM (DLM group), and 37 patients had a semilunar meniscal injury (non-DLM group). The ratio of the lateral femoral condyle, obliquity of the inter-epicondylar line, and prominence ratio in the DLM group were significantly smaller than those in the non-DLM group. On the other hand, no significant difference in the ratio of the medial femoral condyle was observed. Arthroscopic evaluation revealed that the femoral ACL was significantly inserted lower in the DLM group than in the non-DLM group. Conclusion The femoral ACL with DLM was inserted close to the femoral joint surface with morphological abnormality in the knees with DLM related to hypoplasic of the lateral femoral condyle.

Lung fibroblasts participate in the pathogenesis of respiratory diseases, including lung cancer and pulmonary fibrosis. Although fibroblasts are ubiquitous constituents of various organs, their cellular diversity among different organs has been poorly characterized. Here, we aimed to investigate the distinct gene signature of lung fibroblasts that represents its pulmonary origin and the underlying gene regulatory networks. Promoter-level differential expression analysis by cap analysis of gene expression (CAGE) sequencing revealed distinct gene expression patterns of fibroblasts derived from different anatomical sites and identified 88 coding genes with higher expression in lung fibroblasts relative to other fibroblasts. Multiple key transcription factors important for lung mesenchyme development, including the T-box transcription factors TBX2, TBX4, and TBX5 were enriched in this lung-specific signature and were associated with super-enhancers. TBX4 showed highly specific expression in lung fibroblasts and was required for cell proliferation and collagen gel contraction capacity. Transcriptome analysis revealed that TBX4 could broadly regulate fibroblast-related pathways and partly contribute to super-enhancer-mediated transcriptional programs. Of pathological importance, lung fibroblast-specific genes were globally downregulated in lung cancer-associated fibroblasts (CAFs). Notably, TBX2, TBX4, and TBX5 were downregulated and hypermethylated in lung CAFs, suggesting an association between epigenetic silencing of these factors and phenotypic alteration of lung fibroblasts in cancer. Our study highlights the importance of T-box transcription factors, especially TBX4, and super-enhancers in the roles of lung fibroblasts in pulmonary physiology and pathogenesis.

Lung cancer is the leading cause of cancer-related deaths worldwide. The majority of cancer driver mutations have been identified; however, relevant epigenetic regulation involved in tumorigenesis has only been fragmentarily analyzed. Epigenetically regulated genes have a great theranostic potential, especially in tumors with no apparent driver mutations. Here, epigenetically regulated genes were identified in lung cancer by an integrative analysis of promoter-level expression profiles from Cap Analysis of Gene Expression (CAGE) of 16 non–small cell lung cancer (NSCLC) cell lines and 16 normal lung primary cell specimens with DNA methylation data of 69 NSCLC cell lines and 6 normal lung epithelial cells. A core set of 49 coding genes and 10 long noncoding RNAs (lncRNA), which are upregulated in NSCLC cell lines due to promoter hypomethylation, was uncovered. Twenty-two epigenetically regulated genes were validated (upregulated genes with hypomethylated promoters) in the adenocarcinoma and squamous cell cancer subtypes of lung cancer using The Cancer Genome Atlas data. Furthermore, it was demonstrated that multiple copies of the REP522 DNA repeat family are prominently upregulated due to hypomethylation in NSCLC cell lines, which leads to cancer-specific expression of lncRNAs, such as RP1-90G24.10, AL022344.4, and PCAT7. Finally, Myeloma Overexpressed (MYEOV) was identified as the most promising candidate. Functional studies demonstrated that MYEOV promotes cell proliferation, survival, and invasion. Moreover, high MYEOV expression levels were associated with poor prognosis. Implications: This report identifies a robust list of 22 candidate driver genes that are epigenetically regulated in lung cancer; such genes may complement the known mutational drivers. Visual Overview: http://mcr.aacrjournals.org/content/molcanres/15/10/1354/F1.large.jpg. Mol Cancer Res; 15(10); 1354–65. ©2017 AACR.

Key Clinical Message Popliteal artery occlusion after total knee arthroplasty is rare (0.03–0.17%) but can lead to amputation if overlooked. We should carefully assess vascular patency by Doppler ultrasound and ankle brachial pressure index (ABPI) measurement before and after total knee arthroplasty (TKA) operation.

Periodontitis is a chronic inflammatory disease that affects the interface of teeth and surrounding tissues. Gingival crevicular fluid (GCF) is an exudate of the periodontal tissues and can be collected from the gap between the tooth and gum (gingival sulcus or periodontal pocket) with paper strips. Testing of GCF is a low‐cost and minimally invasive procedure. In a variety of diseases, microRNAs (miRNAs) in body fluids are implicated in pathogenesis, and are suggested as potential diagnostic biomarkers. Here, we profiled miRNAs in GCF (two chronic periodontitis, one aggressive periodontitis, and five healthy subjects) using miRCURY LNA™ Universal RT microRNA PCR System, which yielded quantitative measures of more than 600 miRNAs. Through this analysis, we found that miRNA profiles in GCF of periodontitis patients are distinct from those of healthy controls. We further selected 40 miRNAs and confirmed their differential expression patterns in different subjects (five chronic periodontitis, one aggressive periodontitis, and six healthy subjects) using a custom miRNA PCR panel. This is the first demonstration of miRNA profiling in GCF and its alteration in periodontitis. Our findings suggest that a subset of miRNAs in GCF holds potential as a biomarker for periodontitis.

Background Extrusion of the meniscus has been reported to be correlated with progression of osteoarthritis. In cases with osteochondral lesions after extrusion of the meniscus, meniscal transplantation was the only surgical intervention. Recently, a novel procedure called arthroscopic centralisation has been developed to restore the meniscus function by centralising the midbody of the extruded meniscus onto the rim of the tibial plateau using suture anchors. Case report A combination of novel techniques—retrograde osteochondral autograft transplantation to retain hyaline articular cartilage and arthroscopic centralisation to restore residual meniscal function—was used to repair an osteochondral lesion of the lateral tibial plateau possibly caused by extrusion of the lateral meniscus. Good clinical and radiographic outcomes were achieved at the 2-year follow-up. Conclusion A combination of retrograde osteochondral autograft transplantation and arthroscopic centralisation can be a good option to treat the osteochondral lesion of the tibial plateau caused by extrusion of the meniscus.

Multiple microRNAs (miRNAs) regulate epithelial-mesenchymal transition and endothelial-mesenchymal transition (EndMT). Here we report that microRNA-27b (miR-27b) positively regulates transforming growth factor-β (TGF-β)-induced EndMT of MS-1 mouse pancreatic microvascular endothelial cells. TGF-β induced miR-23b/24-1/27b expression, and inhibition of miR-27 suppressed TGF-β-mediated induction of mesenchymal genes. Genome-wide miRNA target analysis revealed that miR-27 targets Elk1, which acts as a competitive inhibitor of myocardin-related transcription factor-serum response factor signalling and as a myogenic repressor. miR-27b was also found to regulate several semaphorin receptors including Neuropilin 2, Plexin A2 and Plexin D1. These results suggest important roles of miR-27 in TGF-β-driven EndMT.

Complex degenerative tears of the medial meniscus in the knee are usually treated using meniscectomy. However, this procedure increases the risk of osteoarthritis, while other treatments aimed at meniscal repair remain challenging due to the high possibility of failure. The use of synovial mesenchymal stem cells (MSCs) is an attractive additional approach for meniscal repair, as these cells have high proliferative and chondrogenic potential. In this case report, we surgically repaired a complex degenerative tear of the medial meniscus and then transplanted autologous synovial MSCs. We evaluated clinical outcomes at 2 years and assessed adverse events. We enrolled patients with clinical symptoms that included a feeling of instability in addition to pain caused by their complex degenerative tears of the medial meniscus. Two weeks after surgical repair of the torn meniscus, autologous synovial MSCs were transplanted onto the menisci of five patients. The total Lysholm knee score, the Knee Injury and Osteoarthritis Outcome Scale scores for “pain,” “daily living,” “sports activities,” and the Numerical Rating Scale were significantly increased after 2 years. Three adverse events, an increase in c-reactive protein, joint effusion, and localized warmth of the knee were recorded, although these could have been due to the meniscal repair surgery. This first-in-human study confirmed that the combination of surgical repair and synovial MSC transplantation improved the clinical symptoms in patients with a complex degenerative tear of the medial meniscus. No adverse events occurred that necessitated treatment discontinuation. These findings will serve as pilot data for a future prospective study.

Background: Transcriptional co-activator with PDZ-binding motif (TAZ) and Yes-associated protein (YAP) are key downstream effectors of the Hippo pathway. TAZ is considered as a homolog of YAP. Recent studies revealed that TAZ knockout mice exhibit lung emphysema, while YAP knockout mice show abnormalities in bronchial morphogenesis, and the cause of these differences remains unknown. Objective: To compare the role of TAZ and YAP in lung development, by generating lung epithelial-specific conditional knockout mice (cKO mice) of Taz and Yap. Methods: Taz and Yap cKO mice were generated by using a surfactant protein C-driven Cre recombinase allele. To identify genes affected by Yap ablation from lung epithelial cells, RNA-seq analysis was performed in Yap cKO embryo lung. We confirmed our in vivo findings by using human lung epithelial cell lines, which YAP and TAZ were suppressed by siRNA. Results: In lung development, Yap was highly expressed in embryonic stage of lung development, conversely Taz was highly expressed in the early alveolar stage. Taz cKO adult mice exhibited lung emphysema in adults, whereas Yap cKO mice were lethal at birth and showed bronchial branching abnormalities. RNA-seq analysis revealed that YAP ablation decreased Sonic hedgehog (Shh) expression, which is essential in proper branching morphogenesis. We also found that TGF-beta stimulation induces Shh expression in cell lines, which was suppressed by knockdown of TAZ or YAP. Conclusion: Our results indicate that TAZ and YAP function at different stages of lung development in lung epithelial cells and essential for proper lung development. Our results suggested the existence of a novel pathway between TGF-beta and Shh.

Exact knowledge of risk factors for residual anterolateral rotatinoal instability (ALRI) after anterior cruciate ligament (ACL) reconstruction is limited. The purpose of this study was to analyse possible risk factors for ALRI after ACL reconstruction.Quantitative assessment of the pivot shift phenomenon by measuring tibial acceleration was performed in 46 patients during primary double-bundle ACL reconstructions. The absolute value of the acceleration of the injured knee after provisional fixation of the ACL grafts ('absolute residual acceleration') and the subtraction of the acceleration of the uninjured knee from absolute residual acceleration ('relative residual acceleration') were defined as indicators for residual ALRI. The associations between these indicators and nine candidate risk factors were analysed using univariate and multiple regression analyses.Multiple regression analysis revealed that absolute residual acceleration was positively associated with both preoperative acceleration difference between injured and uninjured knees (β = 0.469, P 0.001) and tibial acceleration of the uninjured knee (β = 0.597, P 0.001). Relative residual acceleration was also positively associated with preoperative acceleration difference between injured and uninjured knees (β = 0.446, P 0.001), but was negatively associated with tibial acceleration of the uninjured knee (β = -0.763, P 0.001).Patients with larger preoperative side-to-side difference of the pivot shift phenomenon have higher risk for both absolute and relative residual ALRIs after ACL reconstruction, whereas patients with larger pivot shift phenomenon in their uninjured knees are at higher risk for absolute residual ALRI but not for relative residual ALRI.

To compare the position and direction of femoral and tibial tunnels for both the anteromedial bundle (AMB) and posterolateral bundle (PLB) among three different femoral tunnel drilling techniques, transtibial (TT), transportal (TP), and outside-in (OI) techniques, in anatomic double-bundle ACL reconstruction to clarify advantages and disadvantages of each technique. One-hundred and thirty-nine patients underwent primary ACL reconstruction with an autologous semitendinosus tendon in our institution between 2014 and 2016. Thirteen patients were excluded according to the exclusion criteria. Of the 126 patients, 98 patients agreed to be included in this study. Patients were then randomized into three groups according to the femoral tunnel drilling technique; the TT, TP, and OI groups. Femoral and tibial tunnel angles and positions were measured using three-dimensional computed tomography. Of patients who agreed to be included in this study, eight patients (seven in TT and one in OI) were excluded since the femoral tunnel could not be created at the intended position. Eighty-six patients (29 in TT, 29 in TP, and 28 in OI) were included for the analyses. Tunnel angles, as well as tunnel lengths, had significant differences among different techniques depending on each technique’s characteristics. In terms of tunnel position, femoral tunnel positions of both the AMB and PLB in the TT group were significantly higher than those in the TP group (AMB: p = 0.003, PLB: p = 0.001), and the PLB tunnel position in the TP group had significantly smaller vaciance than that in the TT group (p = 0.004) and OI group (0.002). The femoral tunnel positions created by the TT technique were significantly higher, with larger variance, than the TP technique in double-bundle ACL reconstruction, although the positions seemed to be within anatomical footprint. In addition, there were several cases in which femoral tunnels could not be created at the intended position by the TT technique. I

Small cell lung cancer (SCLC) is a highly aggressive and metastatic malignancy that shows rapid development of chemoresistance and a high rate of recurrence. Recent genome and transcriptome studies have provided the whole landscape of genomic alterations and gene expression changes in SCLC. In light of the inter-individual heterogeneity of SCLC, subtyping of SCLC might be helpful for prediction of therapeutic response and prognosis. Based on the transcriptome data of SCLC cell lines, we undertook transcriptional network-defined SCLC classification and identified a unique SCLC subgroup characterized by relatively high expression of Hippo pathway regulators Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) (YAP/TAZ subgroup). The YAP/TAZ subgroup displayed adherent cell morphology, lower expression of achaete-scute complex homolog 1 (ASCL1) and neuroendocrine markers, and higher expression of laminin and integrin. YAP knockdown caused cell morphological alteration reminiscent of floating growth pattern in many SCLC cell lines, and microarray analyses revealed a subset of genes regulated by YAP, including Ajuba LIM protein (AJUBA). AJUBA also contributed to cell morphology regulation. Of clinical importance, SCLC cell lines of the YAP/TAZ subgroup showed unique patterns of drug sensitivity. Our findings shed light on a subtype of SCLC with YAP and TAZ expression, and delineate molecular networks underlying the heterogeneity of SCLC.

Background Infections are an important cause of morbidity and mortality in patients with rheumatoid arthritis. Patients receiving immunosuppressive or anti-tumor necrosis factor (TNF) agents are vulnerable to fungal infections, including those derived from Aspergillus species. Detection of the Aspergillus galactomannan antigen in serum is useful for the early diagnosis of invasive aspergillosis in patients with hematological malignancies. However, its usefulness for detecting early invasive aspergillosis in rheumatoid arthritis patients remains unestablished. Methods Galactomannan antigen levels were measured in 340 patients (311 female patients). For patients who exhibited galactomannan antigen levels ≥0.5 during the initial examination, a second examination was performed 3–6 months later. Conventional blood tests and chest radiography were also performed. Results Elevated galactomannan antigen levels (≥0.5) were observed in 62 (18.2%) of 340 patients during the initial examination. A second examination was performed in 56 of 62 patients, 50 of whom exhibited elevated antigen levels. Elevated antigen levels were not associated with the use of any drug including anti-TNF agents. Serum galactomannan antigen levels were correlated with the albumin/globulin ratio ( r =−0.19, p r =0.17, p =0.001), and hemoglobin concentration ( r =−0.15, p =0.005). No patient was clinically diagnosed with invasive aspergillosis during the study period. Conclusions Serum galactomannan antigen levels are frequently elevated in a nonspecific manner in patients with rheumatoid arthritis.

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic lung disease of unknown etiology and dismal prognosis. IPF patients are known to have an increased risk of lung cancer and careful decision-making is required for the treatment of lung cancer associated with IPF. Transforming growth factor (TGF)-β signaling plays a central role in tissue fibrosis and tumorigenesis. TGF-β-mediated pathological changes that occur in IPF lung tissue may promote the process of field cancerization and provide the microenvironment favorable to cancer initiation and progression. This review summarizes the current knowledge related to IPF pathogenesis and explores the molecular mechanisms that underlie the occurrence of lung cancer in the background of IPF, with an emphasis on the multifaceted effects of TGF-β signaling.

Background: Some types of meniscus tear, especially lateral meniscus tear, have been reported to be associated with rotatory knee laxity. However, precise information regarding the effect of meniscus repair on rotatory laxity is limited. The purpose of this study was to investigate the effects of lateral and medial meniscus repair on rotatory laxity in anterior cruciate ligament (ACL) injured knees. Methods: Forty-one patients who underwent ACL reconstruction were included in the study. The tibial acceleration during the pivot shift test was measured using a triaxial accelerometer preoperatively under anesthesia and intraoperatively before and after medial and lateral meniscus repair and ACL reconstruction during surgery. Effects of meniscus tear and its repair on rotatory laxity were analyzed. Results: Preoperative measurements revealed that patients with lateral meniscus tear showed significantly higher tibial acceleration compared to the patients without meniscus tear (P = 0.006). Intraoperative measurements revealed that medial and lateral meniscus repair significantly reduced tibial acceleration by 1.46 m/s2 (P = 0.002) and 1.91 m/s2 (P < 0.001), respectively. Conclusion: In ACL injured knees, knees with lateral meniscus tear showed greater rotatory laxity compared to the knees without meniscus tear. In addition, lateral meniscus repair, and to a lesser degree medial meniscus repair, reduced rotatory laxity during ACL reconstruction surgery. Therefore, the meniscus should be repaired as much as possible for its role as a secondary stabilizer of rotatory laxity. Besides, the effect of meniscus repair on rotatory laxity should be considered when the indication of anterolateral augmentation is determined.

Phenotypic plasticity of endothelial cells underlies cardiovascular system development, cardiovascular diseases, and various conditions associated with organ fibrosis. In these conditions, differentiated endothelial cells acquire mesenchymal-like phenotypes. This process is called endothelial-mesenchymal transition (EndMT) and is characterized by downregulation of endothelial markers, upregulation of mesenchymal markers, and morphological changes. EndMT is induced by several signaling pathways, including transforming growth factor (TGF)-β, Wnt, and Notch, and regulated by molecular mechanisms similar to those of epithelial-mesenchymal transition (EMT) important for gastrulation, tissue fibrosis, and cancer metastasis. Understanding the mechanisms of EndMT is important to develop diagnostic and therapeutic approaches targeting EndMT. Robust induction of EndMT in vitro is useful to characterize common gene expression signatures, identify druggable molecular mechanisms, and screen for modulators of EndMT. Here, we describe an in vitro method for induction of EndMT. MS-1 mouse pancreatic microvascular endothelial cells undergo EndMT after prolonged exposure to TGF-β and show upregulation of mesenchymal markers and morphological changes as well as induction of multiple inflammatory chemokines and cytokines. Methods for the analysis of microRNA (miRNA) modulation are also included. These methods provide a platform to investigate mechanisms underlying EndMT and the contribution of miRNAs to EndMT.

Background: Bronchial asthma is a chronic airway disease characterized by eosinophilic airway inflammation. Lung fibroblasts activated by IL-13 serve as important sources of chemokines, such as eotaxins, contributing to persistent eosinophilic inflammation. Src-homology 2-containing protein (CISH), belonging to the suppressor of cytokine signaling (SOCS) family, acts as a negative regulator of cytokine induction. The aim of this study was to elucidate the role of CISH in the production of eosinophil chemotactic chemokines in human lung fibroblasts. Methods: Normal human lung fibroblasts were stimulated by IL-13, and global gene expression profile was assessed by cDNA microarray. Expression changes and downstream of IL-13 signaling were evaluated by quantitative RT-PCR, ELISA or western blotting. Loss- and gain-of-function analyses of CISH were performed by small interfering RNA and vector overexpression, respectively. Results: Ingenuity pathway analysis revealed that IL-13 induced chemokine signaling, including the eotaxin family, while significantly suppressing IFN-α/β signaling. Among eight SOCS family members, CISH was most strongly induced by IL-13 via phosphorylation of signal transducer and activator of transcription 6 (STAT6). Loss- and gain-of-function studies demonstrated that CISH negatively regulated the expression of CCL26. Conclusions: These findings suggest that CISH plays a key role in the eosinophilic inflammation associated with bronchial asthma by regulating IL-13-induced CCL26 production. Augmentation of CISH function could be a novel approach for treating eosinophilic inflammation in severe asthma. Keywords: Asthma, Eotaxin-3, Fibroblast, Interleukin-13, Transcriptome

A subgroup of lung adenocarcinoma shows neuroendocrine differentiation and expression of achaete-scute family bHLH transcription factor 1 (ASCL1), common to high-grade neuroendocrine tumors, small-cell lung cancer and large cell neuroendocrine carcinoma.The aim of this study was to characterize clinical and molecular features of ASCL1-positive lung adenocarcinoma by using recent transcriptome profiling in multiple patient cohorts and genome-wide epigenetic profiling including data from The Cancer Genome Atlas.The ASCL1-positive subtype of lung adenocarcinoma developed preferentially in current or former smokers and usually did not harbor EGFR mutations. In transcriptome profiling, this subtype overlapped with the recently proposed proximal-proliferative molecular subtype. Gene expression profiling of ASCL1-positive cases suggested generally poor immune cell infiltration and none of the tumors were positive for programmed cell death ligand 1 protein expression. Genome-wide methylation analysis showed global DNA hypomethylation in ASCL1-positive cases. ASCL1 was associated with super-enhancers in ASCL1-positive lung adenocarcinoma cells, and ASCL1 silencing suppressed other super-enhancer-associated genes, suggesting that ASCL1 acts as a master transcriptional regulator. This was further reinforced by the essential roles of ASCL1 in cell proliferation, survival, and cell cycle control.These results suggest that ASCL1 defines a subgroup of lung adenocarcinoma with distinct molecular features by driving super-enhancer-mediated transcriptional programs.

To investigate the risk factors for residual pivot shift test after anterior cruciate ligament (ACL) reconstruction based on a multicenter prospective cohort study. This study included patients who were registered in the Multicenter Arthroscopic Knee Surgery Study, a prospective longitudinal multicenter cohort study, and who underwent primary ACL reconstruction using autologous hamstring tendon graft between 2013 and 2016. The exclusion criteria included prior injuries or surgeries in the contralateral knee, prior ligamentous injuries in the involved knee, grade 2 or 3 concomitant ligament injuries, and inflammatory or other forms of osteoarthritis. Data from the preoperative period and at 1-year follow-up were used for further analysis, and patients with incomplete data, re-injury and loss to follow-up were also excluded. Logistic regression analysis was conducted with age, gender, Lachman test, pivot shift test, KT measurement, hyperextension, single-bundle vs. double-bundle, meniscus injury sites, and meniscus treatments as the independent variables, and postoperative pivot shift test was used as the dependent variable. Three hundred and sixty-eight patients were included in the study. Hyperextension knee (P = 0.025) and a preoperative pivot shift test under anesthesia (P = 0.040) were identified as risk factors for a postoperative pivot shift via logistic regression analysis. There were no statistically significant differences in the other variables. The results from a multicenter cohort study indicated that knee hyperextension and greater preoperative pivot shift under anesthesia were risk factors for residual pivot shift at 1 year after ACL reconstruction. In cases with a preoperative high-grade pivot shift and knee hyperextension, additional anterolateral structure augmentation might be considered in order to eliminate pivot shift and eventually obtain better outcomes after ACL reconstruction. II.

Hypoplastic meniscus is an extremely rare abnormality. The authors present the first case of meniscal hypoplasia with a partial fusion of meniscus and tibial cartilage. A 22-year-old man underwent surgery for a chronic patellar dislocation. Preoperative magnetic resonance imaging and arthroscopy incidentally revealed hypoplasia of both medial and lateral menisci. Moreover, the posterior horn of the medial meniscus and middle body of the lateral meniscus were fused with the cartilage surface of the tibia. Magnetic resonance imaging of the contralateral knee showed similar meniscal anomalies. This case presents an interesting and extremely rare abnormality of the meniscus. [ Orthopedics . 2018; 41(6):e884–e887.]

Background Patients with primary spontaneous pneumothorax (PSP) usually complain of sudden-onset dyspnea and pleuritic chest pain. However, asymptomatic PSP has been incidentally detected on chest X-rays. In this study, we analyzed the incidence, characteristics, risk factors, and prognosis of asymptomatic PSP detected during regular medical check-ups in university students. Methods In this study, 101,709 chest X-rays were performed during medical check-ups for students at the University of Tokyo between April 2011 and March 2016. Among them, 43 cases of asymptomatic PSP (0.042%) were detected. We calculated the lung collapse rate of pneumothorax using Kircher’s method. We also analyzed risk factors associated with asymptomatic PSP using characteristics inspected in medical check-ups. Results The incidence of asymptomatic PSP was significantly higher in men than in women (0.050% vs 0.018%). Multivariate analysis revealed an association of younger age, greater height, lower body mass index, and greater height growth per year with an increased risk of asymptomatic PSP in male students. Mild lung collapse (

Evaluating pivot shift phenomenon is difficult due to its subjectivity, wide variation of testing manoeuvres, and difficulty in evaluating patients while awake. The purpose of this study was to evaluate the pivot shift phenomenon using a triaxial accelerometer by two different manoeuvres, the pivot shift test as representative of flexion manoeuvre and N test as a representative of extension manoeuvre, and in two different conditions, awake and under anaesthesia.Twenty-nine patients with unilateral anterior cruciate ligament (ACL)-injured knee were included. Pivot shift test and N test were performed for both injured and uninjured legs while awake and under anaesthesia, with the acceleration measurements using a triaxial accelerometer (KiRA). The tests were also subjectively graded on a scale of 0-6 based on the modification of IKDC criteria.Under anaesthesia, acceleration of ACL-injured knees was greater than that of uninjured knees in both pivot shift test (P 0.001) and N test (P 0.001) , whereas the acceleration value was greater in the N test. Furthermore, there were significant positive correlations between the acceleration and subjective grading in both tests, whereas the N test was more significant than the pivot shift test. On the other hand, there was no statistical significance in acceleration between ACL-injured and uninjured knees in either test while the patient was awake.The triaxial accelerometer was useful to objectively detect and quantitatively evaluate the pivot shift phenomenon by both the pivot shift test and N test under anaesthesia. The acceleration of ACL-injured knees was greater than that of uninjured knees, and the acceleration was correlated with the subjective manual grading, especially in the N test. On the other hand, its use while the patient was awake was likely limited.Diagnostic study of non-consecutive patients without a universally applied gold standard, Level III.

To describe the femoral anterior cruciate ligament (ACL) attachment based on the behind-remnant observation with a new scoring system and to investigate the characteristics of an ACL injured knee. One hundred and twenty-six ACL injured knees with four standardized arthroscopic photos and full evaluation under anaesthesia were included in the study. Sixty non-ACL injured knees were also evaluated as control. A scoring system for the femoral ACL attachment was set as follows based on behind-remnant findings; the direct insertion was divided into three portions as proximal, middle and distal. The fibrous extension from the articular surface (indirect insertion) and the severity of synovitis were also graded into 2, 1 and 0 points. The total score was 10 as full marks. The correlation between each score and total score, as well as age at surgery, gender, anterior laxity, pivot-shift test and meniscus injuries, was statistically evaluated with a significance of 0.05. The femoral attachment score of the ACL injured knees was statistically different from that of the non-ACL injured knees. Anterior laxity was dependent only on the integrity of the proximal portion. Knee instability was significantly correlated with the status of the direct insertion. Medial and lateral meniscus injuries were correlated with the middle part and the distal part of the direct insertion, respectively. The direct insertion was less preserved in distal and articular sides. Arthroscopic observation behind the remnant of the injured ACL showed clearer findings of the femoral attachment than that from the front. Behind-remnant observation greatly assists in the creation of a correct anatomical tunnel with the preserving remnant. The scoring system indicated several significant correlations between the score and preoperative patient status.

To evaluate the mid-to long-term results of a randomized controlled trial of single-bundle (SB) versus double-bundle (DB) anterior cruciate ligament (ACL) reconstruction using a semitendinosus tendon.Seventy-eight patients who underwent primary ACL reconstruction with an autologous semitendinosus tendon were prospectively randomized into 2 groups: SB reconstruction (n = 39) and DB reconstruction (n = 39). In both groups, grafts were fixed at 30° of flexion with a total tension of 80 N. The following evaluation methods were used: clinical examination, KT-1000 arthrometer (MEDmetric, San Diego, CA) measurement, muscle strength, Tegner activity score, Lysholm score, subjective rating scale regarding patient satisfaction and sports performance level, graft retear, contralateral ACL tear, and additional meniscus surgery.Fifty-three patients (25 in SB group and 28 in DB group) who were followed up for a minimum of 3 years (mean, 69 months; range, 36 to 140 months) were evaluated. Preoperatively, there were no differences between the groups. Postoperatively, the Lachman and pivot-shift test results were better in the DB group (P = .024 and P.0001, respectively). KT measurements were better in the DB group (mean, 1.4 mm v 2.7 mm; P = .0023). The Tegner score was also better in the DB group (P = .033). There were no significant differences in range of motion, muscle strength, Lysholm score, subjective rating scale, graft retear, and secondary meniscal tear.In ACL reconstruction using the transtibial approach, DB reconstruction was significantly better than SB reconstruction regarding anterior and rotational stability during the 3- to 12-year follow-up. The results of KT measurements and the Lachman and pivot-shift tests were significantly better in the DB group, whereas there was no difference in the anterior drawer test results. The Tegner score was also better in the DB group; however, there were no differences in the other subjective findings.Level II, lesser-quality prospective randomized trial.

Small cell lung cancer (SCLC) is a neuroendocrine tumour that exhibits rapid growth and metastatic spread. Although SCLC represents a prototypically undifferentiated cancer type, thyroid transcription factor-1 (TTF-1, gene symbol NKX2-1), a master regulator for pulmonary epithelial cell differentiation and lung morphogenesis, is strongly upregulated in this aggressive cancer type. The aim of this study was to evaluate a functional role for TTF-1 in SCLC. We demonstrated that achaete-scute complex homolog 1 (ASCL1), an essential transcription factor for neuroendocrine differentiation, positively regulated TTF-1 in SCLC cell lines. Subsequently, we described genes and microRNAs (miRNAs) that were possibly controlled by TTF-1 and identified nuclear factor IB (NFIB), a recently characterised driver of SCLC progression, as a transcriptional target of TTF-1. Our findings shine light on a regulatory axis in SCLC consisting of ASCL1/TTF-1/NFIB that potentially contributes to the tumourigenesis of SCLC. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John WileySons, Ltd.

Introduction: Naftopidil, a selective α1 adrenoceptor antagonist, inhibits the growth of prostate fibroblasts by inducing cell apoptosis without the blocking effects of α1 adrenoceptor. However, the effects of naftopidil are little known on the growth of lung fibroblast and lung fibrosis. Methods: We examined the effects of naftopidil on the growth of lung fibroblasts using 5-Bromo-29-deoxyuridine (BrdU) incorporation assay. We also examined whether naftopidil induced the apoptosis of lung fibroblasts by analyzing the levels of cleaved caspase-3 by Western blotting. The effects of naftopidil on bleomycin-induced lung fibrosis in mice were examined. Results: Naftopidil inhibited the growth of lung fibroblasts in a dose-dependent manner. This inhibitory effect was weakened in lung fibroblast derived from a patient with idiopathic pulmonary fibrosis in comparison to normal human lung fibroblasts. Western blotting revealed that naftopidil induced the apoptosis of lung fibroblasts similarly to prostate fibroblasts. Naftopidil also attenuated bleomycin-induced lung fibrosis in mice. Conclusions: Naftopidil, a selective α1 adrenoceptor antagonist, inhibits the growth of lung fibroblasts by inducing cell apoptosis and attenuates bleomycin-induced lung fibrosis in mice.

The meniscus roots are critical for meniscus function in preserving correct knee kinematics and avoiding meniscus extrusion and, consequently, in the progression of osteoarthritis. Several techniques exist for medial meniscus posterior root tear repair; however, current surgical techniques have been proved to fail to reduce meniscus extrusion, which has been shown to be associated with development of osteoarthritis, although significant improvements in the postoperative clinical findings have been achieved. This Technical Note describes an arthroscopic technique for the medial meniscus posterior root tear in which a pullout repair is augmented by a centralization technique to restore and maintain the medial meniscus function by efficiently reducing meniscus extrusion.

Background: Asthma is a chronic airway inflammatory disease characterized by airway remodeling, in which the bronchial smooth muscle (BSM) cells play an important role. Periostin, a biomarker that reflects Th2-driven inflammatory diseases such as asthma, may play an important role in the asthmatic airway. Although periostin is mainly produced in airway epithelial cells and fibroblasts after interleukin (IL)-13 stimulation, whether BSM cells produce periostin remains unclear. Therefore, we investigated periostin production in BSM cells and the mechanisms involved. Methods: Human BSM cells were cultured, and the effect of IL-13 stimulation on periostin production was evaluated using quantitative polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA). We evaluated the phosphorylation of signal transducer and activator of transcription factor 6 (STAT6), extracellular signal-regulated kinase (ERK)1/2, and Akt after IL-13 stimulation. Furthermore, using ELISA, we evaluated the influence of several phosphorylation inhibitors on periostin production. Results: Periostin mRNA expression increased in a dose- and time-dependent manner after IL-13 stimulation; periostin production was induced 24 and 48 h after stimulation. IL-13 stimulation induced the phosphorylation of STAT6, ERK1/2, and Akt. IL-13-induced periostin production was attenuated by inhibiting STAT6 phosphorylation and strongly suppressed by inhibiting mitogen-activated protein kinase kinase 1/2 phosphorylation or phosphatidylinositol 3-kinase (PI3K) phosphorylation. Conclusions: BSM cells produced periostin after IL-13 stimulation, via the JAK/STAT6, ERK1/2, and PI3K/Akt pathways. Understanding the mechanism of periostin production in BSM cells may help to clarify asthma pathogenesis.

Background The post-cam mechanism in posterior stabilized (PS) prostheses plays an important role in total knee arthroplasty (TKA). The purpose of this study is to clarify the difference of the contact stress on the tibial post between a rounded post-cam design and a squared design during deep knee flexion and at hyperextension using the three-dimensional (3D) finite element models. Methods We created 2 types of 3D, finite element models of PS prostheses (types A and B), whose surfaces were identical except for the post-cam geometries: type A has a rounded post-cam design, while type B has a squared design. Both types have a similar curved-shape intercondylar notch of the femoral component. Stress distributions, peak contact stresses, and contact areas on the tibial posts at 90°, 120°, and 150° flexion with/without 10° tibial internal rotation and at 10° hyperextension were compared between the 2 models. Results Type B demonstrated more concentrated stress distribution compared to type A. The peak contact stresses were similar in both groups during neutral flexion; however, the stresses were much higher in type B during flexion with 10° rotation and at hyperextension. The higher peak contact stresses corresponded to the smaller contact areas in the tibial post. Conclusion A rounded post-cam design demonstrated less stress concentration during flexion with rotation and at hyperextension compared with a squared design. The results would be useful for development of implant designs and prediction of the contact stress on the tibial post in PS total knee arthroplasty.

The purposes of this study were to investigate (1) meniscus status and clinical findings in anterior cruciate ligament (ACL)-injured patients to clarify associations between the meniscus posterior root tear (PRT) and knee instability, and (2) magnetic resonance imaging (MRI) findings of the PRT to clarify sensitivity and specificity of MRI and prevalence of meniscus extrusion. Three hundred and seventeen patients with primary ACL reconstruction were included. PRTs for both medial and lateral sides were confirmed by reviewing surgical records. Preoperative MRI was reviewed to evaluate sensitivity and specificity of the PRT and meniscus extrusion width (MEW). Clinical information regarding the number of giving-way episodes, preoperative KT-1000 measurements and preoperative pivot shift was also assessed. Thirty-nine patients had a lateral meniscus (LM) PRT, whereas only four patients had a medial meniscus PRT. One hundred and seventeen patients had no meniscus tear (control). Twenty-eight patients (71.8%) showed positive signs of the LMPRT based on at least one view of MR images, with the coronal view showing the highest sensitivity. MEW in the LMPRT group was significantly larger than that in the control group. The preoperative pivot shift test grade in the LMPRT group was significantly greater than that in the control group. There were no significant differences in other parameters. In ACL-injured patients, the LMPRT was associated with ALRI as well as with meniscus extrusion. The coronal view of MRI was useful in identifying the LMPRT, although its sensitivity was not high. Therefore, surgeons should prepare to repair PRTs at the time of ACL reconstruction regardless of MRI findings, and they should make every effort to repair the LMPRT. III.

Background Mesenchymal stem cells derived from the synovial membrane (synovial MSCs) are a candidate cell source for regenerative medicine of cartilage and menisci due to their high chondrogenic ability. Regenerative medicine can be expected for RA patients with the inflammation well-controlled as well as OA patients and transplantation of synovial MSCs would also be a possible therapeutic treatment. Some properties of synovial MSCs vary dependent on the diseases patients have, and whether or not the pathological condition of RA affects the chondrogenesis of synovial MSCs remains controversial. The purpose of this study was to compare the properties of primary synovial MSCs between RA and OA patients. Methods Human synovial tissue was harvested during total knee arthroplasty from the knee joints of eight patients with RA and OA respectively. Synovial nucleated cells were cultured for 14 days. Total cell yields, surface markers, and differentiation potentials were analyzed for primary synovial MSCs. Results Nucleated cell number per 1 mg synovium was 8.4 ± 3.9 thousand in RA and 8.0 ± 0.9 thousand in OA. Total cell number after 14-day culture/1 mg synovium was 0.7 ± 0.4 million in RA and 0.5 ± 0.3 million in OA, showing no significant difference between in RA and OA. Cells after 14-day culture were mostly positive for CD44, CD73, CD90, CD105, negative for CD45 both in RA and OA. There was no significant difference for the cartilage pellet weight and sGAG content per pellet between in RA and OA. Both oil red O-positive colony rate and alizarin red-positive colony rate were similar in RA and OA. Conclusions Yields, surface markers and chondrogenic potential of primary synovial MSCs in RA were comparable to those in OA. Synovium derived from RA patients can be the cell source of MSCs for cartilage and meniscus regeneration. Electronic supplementary material The online version of this article (doi:10.1186/s13287-017-0572-8) contains supplementary material, which is available to authorized users.