NLRP3 inflammasome activation triggers severe inflammatory liver injury in N, N-dimethylformamide-exposed mice.

N,N-dimethylformamide (DMF) is a widely utilized chemical solvent with various industrial applications. Previous studies have indicated that the liver is the most susceptible target to DMF exposure, whereas the underlying mechanisms remain to be elucidated. This study aimed to investigate the role of NLRP3 inflammasome in DMF-induced liver injury in mice by using two NLRP3 inflammasome inhibitors, Nlrp3-/- mice, Nfe2l2-/- mice, and a macrophage-depleting agent. RNA sequencing revealed that endoplasmic reticulum (ER) stress and NLRP3 inflammasome-associated pathways were activated in the mouse liver after acute DMF exposure, which was validated by Western blotting. Interestingly, DMF-induced liver injury was effectively suppressed by two inflammasome inhibitors, MCC950 and Dapansutrile. In addition, knockout of Nlrp3 markedly attenuated DMF-induced liver injury without affecting the metabolism of DMF. Furthermore, silencing Nfe2l2 aggravated the liver injury and the NLRP3 inflammasome activation in mouse liver. Finally, the depletion of hepatic macrophages by clodronate liposomes significantly reduced the liver damage caused by DMF. These results suggest that NLRP3 inflammasome activation is the upstream molecular event in the development of acute liver injury induced by DMF.

Tannic Acid-Modified Decellularized Tendon Scaffold with Antioxidant and Anti-Inflammatory Activities for Tendon Regeneration.

Tendon regeneration is greatly influenced by the oxidant and the inflammatory microenvironment. Persistent inflammation during the tendon repair can cause matrix degradation, tendon adhesion, and excessive accumulation of reactive oxygen species (ROS), while excessive ROS affect extracellular matrix remodeling and tendon integration. Herein, we used tannic acid (TA) to modify a decellularized tendon slice (DTS) to fabricate a functional scaffold (DTS-TA) with antioxidant and anti-inflammatory properties for tendon repair. The characterizations and cytocompatibility of the scaffolds were examined in vitro. The antioxidant and anti-inflammatory activities of the scaffold were evaluated in vitro and further studied in vivo using a subcutaneous implantation model. It was found that the modified DTS combined with TA via hydrogen bonds and covalent bonds, and the hydrophilicity, thermal stability, biodegradability, and mechanical characteristics of the scaffold were significantly improved. Afterward, the results demonstrated that DTS-TA could effectively reduce inflammation by increasing the M2/M1 macrophage ratio and interleukin-4 (IL-4) expression, decreasing the secretion of interleukin-6 (IL-6) and interleukin-1ß (IL-1ß), as well as scavenging excessive ROS in vitro and in vivo. In summary, DTS modified with TA provides a potential versatile scaffold for tendon regeneration.

Allyl methyl disulfide (AMDS) prevents N,N-dimethyl formamide-induced liver damage by suppressing oxidative stress and NLRP3 inflammasome activation.

N,N-dimethylformamide (DMF), a widely consumed industrial solvent with persistent characteristics, can induce occupational liver damage and pose threats to the general population due to the enormous DMF-containing industrial efflux and emission from indoor facilities. This study was performed to explore the roles of allyl methyl disulfide (AMDS) in liver damage induced by DMF and the underlying mechanisms. AMDS was found to effectively suppress the elevation in the liver weight/body weight ratio and serum aminotransferase activities, and reduce the mortality of mice induced by DMF. In addition, AMDS abrogated DMF-elicited increases in malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) levels and decreases in glutathione (GSH) levels in mouse livers. The increase in macrophage number, mRNA expression of M1 macrophage biomarkers, and protein expression of key components in the NF-κB pathway and NLRP3 inflammasome induced by DMF exposure were all suppressed by AMDS in mouse livers. Furthermore, AMDS inhibited DMF-induced cell damage and NF-κB activation in cocultured AML12 hepatocytes and J774A.1 macrophages. However, AMDS per se did not significantly affect the protein level and activity of CYP2E1. Collectively, these results demonstrate that AMDS effectively ameliorates DMF-induced acute liver damage possibly by suppressing oxidative stress and inactivating the NF-κB pathway and NLRP3 inflammasome.

High-fat diet promotes multiple binges-induced liver injury via promoting hepatic macrophage proinflammatory polarization.

High-fat diet (HFD) and ethanol could synergistically induce liver damage, but the underlying mechanisms remain to be elucidated. M1-polarized macrophages have been demonstrated to be key players in ethanol-induced liver damage. The current study was designed to investigate whether hepatic steatosis could promote ethanol-induced liver injury by promoting liver macrophage M1 polarization. In the in vivo study, 12 weeks of HFD feeding induced a moderate increase in the F4/80 expression and protein levels of p-IKKα/ß, p-IκBα, and p-p65, which was suppressed by single binge. In contrast, 8 weeks of HFD and multiple binges (two binges per week during the last 4 weeks) synergistically increased the F4/80 expression, mRNA levels of M1 polarization biomarkers including Ccl2, Tnfa, and Il1b, and protein levels of p65, p-p65, COX2, and Caspase 1. In the in vitro study, a nontoxic free fatty acids (FFAs) mixture (oleic acid/palmitic acid = 2: 1) induced a moderate increase of protein levels of p-p65 and NLRP3 in murine AML12 hepatocytes, which was inhibited by ethanol co-exposure. Ethanol alone induced proinflammatory polarization of murine J774A.1 macrophages evidenced by the enhanced secretion of TNF-α, increased mRNA levels of Ccl2, Tnfa, and Il1b, and upregulated protein levels of p65, p-p65, NLRP3, and Caspase 1, which was augmented by FFAs exposure. Collectively, these results suggest that HFD and multiple binges could synergistically induce liver damage by promoting the proinflammatory activation of macrophages in mice livers.

Decellularized tendon scaffolds loaded with collagen targeted extracellular vesicles from tendon-derived stem cells facilitate tendon regeneration.

Stem cell-based treatment of tendon injuries remains to have some inherent issues. Extracellular vesicles derived from stem cells have shown promising achievements in tendon regeneration, though their retention in vivo is low. This study reports on the use of a collagen binding domain (CBD) to bind extracellular vesicles, obtained from tendon-derived stem cells (TDSCs), to collagen. CBD-extracellular vesicles (CBD-EVs) were coupled to decellularized bovine tendon sheets (DBTS) to fabricate a bio-functionalized scaffold (CBD-EVs-DBTS). Our results show that thus obtained bio-functionalized scaffolds facilitate the proliferation, migration and tenogenic differentiation of stem cells in vitro. Furthermore, the scaffolds promote endogenous stem cell recruitment to the defects, facilitate collagen deposition and improve the biomechanics of injured tendons, thus resulting in functional regeneration of tendons.

Constructing a highly bioactive tendon-regenerative scaffold by surface modification of tissue-specific stem cell-derived extracellular matrix.

Developing highly bioactive scaffold materials to promote stem cell migration, proliferation and tissue-specific differentiation is a crucial requirement in current tissue engineering and regenerative medicine. Our previous work has demonstrated that the decellularized tendon slices (DTSs) are able to promote stem cell proliferation and tenogenic differentiation in vitro and show certain pro-regenerative capacity for rotator cuff tendon regeneration in vivo. In this study, we present a strategy to further improve the bioactivity of the DTSs for constructing a novel highly bioactive tendon-regenerative scaffold by surface modification of tendon-specific stem cell-derived extracellular matrix (tECM), which is expected to greatly enhance the capacity of scaffold material in regulating stem cell behavior, including migration, proliferation and tenogenic differentiation. We prove that the modification of tECM could change the highly aligned surface topographical cues of the DTSs, retain the surface stiffness of the DTSs and significantly increase the content of multiple ECM components in the tECM-DTSs. As a result, the tECM-DTSs dramatically enhance the migration, proliferation as well as tenogenic differentiation of rat bone marrow-derived stem cells compared with the DTSs. Collectively, this strategy would provide a new way for constructing ECM-based biomaterials with enhanced bioactivity for in situ tendon regeneration applications.

Biomechanically and biochemically functional scaffold for recruitment of endogenous stem cells to promote tendon regeneration.

Tendon regeneration highly relies on biomechanical and biochemical cues in the repair microenvironment. Herein, we combined the decellularized bovine tendon sheet (DBTS) with extracellular matrix (ECM) from tendon-derived stem cells (TDSCs) to fabricate a biomechanically and biochemically functional scaffold (tECM-DBTS), to provide a functional and stem cell ECM-based microenvironment for tendon regeneration. Our prior study showed that DBTS was biomechanically suitable to tendon repair. In this study, the biological function of tECM-DBTS was examined in vitro, and the efficiency of the scaffold for Achilles tendon repair was evaluated using immunofluorescence staining, histological staining, stem cell tracking, biomechanical and functional analyses. It was found that tECM-DBTS increased the content of bioactive factors and had a better performance for the proliferation, migration and tenogenic differentiation of bone marrow-derived stem cells (BMSCs) than DBTS. Furthermore, our results demonstrated that tECM-DBTS promoted tendon regeneration and improved the biomechanical properties of regenerated Achilles tendons in rats by recruiting endogenous stem cells and participating in the functionalization of these stem cells. As a whole, the results of this study demonstrated that the tECM-DBTS can provide a bionic microenvironment for recruiting endogenous stem cells and facilitating in situ regeneration of tendons.

Focal solitary necrotic nodules in fatty liver: characteristics on conventional and contrast-enhanced ultrasonography.

PURPOSE: Focal lesions in fatty liver are difficult to diagnose using conventional ultrasonography (CVUS). The aim of this study was to investigate the characteristics of solitary necrotic nodules (SNNs) in fatty liver using CVUS and contrast-enhanced ultrasonography (CEUS) and to evaluate the diagnostic value of CEUS for SNNs in fatty liver. METHODS: Fifteen SNNs in the fatty liver of fifteen patients were examined by both CVUS and CEUS. The contrast agent SonoVue was used for CEUS. The characterization and shape of these SNNs in the fatty liver were analyzed using CEUS. RESULTS: CVUS revealed eight oval-shaped, six irregularly shaped, and one wedge-shaped SNN in the fatty liver. The six irregularly shaped lesions on CVUS were revealed to comprise four gourd-shaped, one serpiginous, and one 3-pin socket-shaped nodule on CEUS. One of these SNNs showed a subcapsular wedge shape, with peripheral and distinct internal septal hyperenhancement in the arterial phases that washed out in the portal phase; moreover, most areas of th lesion showed no internal enhancement in any of the three phases. Fourteen of the lesions were characterized as lacking internal enhancement, and 12 of them had mild-moderate peripheral thin enhancement in the arterial phases. Twelve of the 15 nodules could be considered for diagnosis as SNNs by CEUS, which was further proved by US-guided biopsy and histopathology. However none of them could be considered for diagnosis as SNNs by CVUS. CONCLUSIONS: CEUS is a valuable tool for visualizing the characteristics of SNNs in fatty liver to improve the differential diagnosis.

Saikosaponin D Alleviates DOX-induced Cardiac Injury In Vivo and In Vitro.

ABSTRACT: As a highly efficient anticancer agent, doxorubicin (DOX) is used for treatment of various cancers, but DOX-induced oxidative damages contribute to a degenerative irreversible cardiac toxicity. Saikosaponin D (SSD), which is a triterpenoid saponin with many biological activities including anti-inflammatory effects and antioxidant properties, provides protection against pathologic cardiac remodeling and fibrosis. In the present study, we investigated the work of SSD for DOX-induced cardiotoxicity and the involved mechanisms. We observed that DOX injection induced cardiac injury and malfunction and decreased survival rate. Besides, DOX treatment increased lactate dehydrogenase leakage, cardiomyocyte apoptosis, and myocardium fibrosis and decreased the size of cardiomyocytes. Meanwhile, all the effects were notably attenuated by SSD treatment. In vitro, we found that 1 µM SSD could enhance the proliferation of H9c2 cells and inhibit DOX-induced apoptosis. It was found that the levels of malondialdehyde (MDA) and reactive oxygen species were significantly reduced by improving the activities of the endogenous antioxidative enzymes including catalase and glutathione peroxidase. Furthermore, SSD treatment could downregulate the DOX-induced p38 phosphorylation. Our results suggested that SSD efficiently protected the cardiomyocytes from DOX-induced cardiotoxicity by inhibiting the excessive oxidative stress via p38-MAPK (mitogen-activated protein kinase, MAPK) signaling pathway.

Enhancement of Migration and Tenogenic Differentiation of Macaca Mulatta Tendon-Derived Stem Cells by Decellularized Tendon Hydrogel.

Decellularized tendon hydrogel from human or porcine tendon has been manufactured and found to be capable of augmenting tendon repair in vivo. However, no studies have clarified the effect of decellularized tendon hydrogel upon stem cell behavior. In the present study, we developed a new decellularized tendon hydrogel (T-gel) from Macaca mulatta, and investigated the effect of T-gel on the proliferation, migration and tenogenic differentiation of Macaca mulatta tendon-derived stem cells (mTDSCs). The mTDSCs were first identified to have universal stem cell characteristics, including clonogenicity, expression of mesenchymal stem cell and embryonic stem cell markers, and multilineage differentiation potential. Decellularization of Macaca mulatta Achilles tendons was confirmed to be effective by histological staining and DNA quantification. The resultant T-gel exhibited highly porous structure or similar nanofibrous structure and approximately swelling ratio compared to the collagen gel (C-gel). Interestingly, stromal cell-derived factor-1 (SDF-1) and fibromodulin (Fmod) inherent in the native tendon extracellular matrix (ECM) microenvironment were retained and the values of SDF-1 and Fmod in the T-gel were significantly higher than those found in the C-gel. Compared with the C-gel, the T-gel was found to be cytocompatible with NIH-3T3 fibroblasts and displayed good histocompatibility when implanted into rat subcutaneous tissue. More importantly, it was demonstrated that the T-gel supported the proliferation of mTDSCs and significantly promoted the migration and tenogenic differentiation of mTDSCs compared to the C-gel. These findings indicated that the T-gel, with its retained nanofibrous structure and some bioactive factors of native tendon ECM microenvironment, represents a promising hydrogel for tendon regeneration.

Analysis of the Relevance of the Ultrasonographic Features of Papillary Thyroid Carcinoma and Cervical Lymph Node Metastasis on Conventional and Contrast-Enhanced Ultrasonography.

BACKGROUND: Preoperative prediction of lymph node metastases has a major impact on prognosis and recurrence for patients with papillary thyroid carcinoma (PTC). Thyroid ultrasonography is the preferred inspection to guide the appropriate diagnostic procedure. PURPOSE: To investigate the relationship between PTC and cervical lymph node metastasis (CLNM, including central and lateral LNM) using both conventional ultrasound (US) and contrast-enhanced ultrasound (CEUS). MATERIAL AND METHODS: Our study retrospectively analyzed 379 patients diagnosed with PTC confirmed by surgical pathology at our hospital who underwent US and CEUS examinations from October 2016 to March 2021. Individuals were divided into two groups: the lymph node metastasis group and the nonmetastasis group. The relationship between US and CEUS characteristics of PTC and CLNM was analyzed. Univariate and multivariable logistic regression methods were used to identify the high-risk factors and established a nomogram to predict CLNM in PTC. Furthermore, we explore the frequency of CLNM at each nodal level in PTC patients. RESULTS: Univariate analysis indicated that there were significant differences in gender, age, tumor size, microcalcification, contact with the adjacent capsule, multifocality, capsule integrity and enhancement patterns in CEUS between the lymph node metastasis group and the nonmetastasis group (all P<0.05). Multivariate regression analysis showed that tumor size ≥1 cm, age ≤45 years, multifocality, and contact range of the adjacent capsule >50% were independent risk factors for CLNM in PTC, which determined the nomogram. The diagnostic model had an area under the curve (AUC) of 0.756 (95% confidence interval, 0.707-0.805). And calibration plot analysis shown that clinical utility of the nomogram. In 162 PTC patients, the metastatic rates of cervical lymph nodes at levels I-VI were 1.9%, 15.4%, 35.2%, 34.6%, 15.4%, 82.1%, and the difference was statistically significant (P<0.001). CONCLUSION: Our study indicated that the characteristics of PTC on ultrasonography and CEUS can be used to predict CLNM as a useful tool. Preoperative analysis of ultrasonographical features has important value for predicting CLNM in PTCs. The risk of CLNM is greater when tumor size ≥1 cm, age ≤45 years, multifocality, contact range of the adjacent capsule >50% are present.

Influence of the integrity of tendinous membrane and fascicle on biomechanical characteristics of tendon-derived scaffolds.

The biomechanical characteristics of tendon grafts is essential for tendon reconstructive surgery due to its great role in providing a good mechanical environment for tendon healing and regeneration. In our previous studies, the decellularized tendon slices (DTSs) and decellularized bovine tendon sheets (DBTSs) scaffolds were successfully developed. However, the influence of the integrity of tendinous membrane (endotenon and epitenon) and fascicle on biomechanical characteristics of these two scaffolds was not investigated. In this study, we assessed the integrity of tendinous membrane and fascicle of the tendon derived scaffolds and its effect on the biomechanical characteristics. The results of histological staining indicated that the DBTSs had complete endotenon and epitenon, while DTSs had no epitenon at all, only part of endotenon was remained. Furthermore, the DBTSs, and DTSs with thickness of 900 µm had complete fascicles, while DTSs with thickness less than 600 µm had almost no complete fascicles. The fibrous configuration of epitenon was well-preserved in the surface of the DBTSs but the surface ultrastructure of the DTSs was aligned collagen fibers based on scanning electron microscopy examination. The results of transmission electron microscopy showed that there was no significant difference between the DBTSs and DTSs. Mechanically, the DBTSs and DTSs with thickness of 900 µm showed similar ultimate tensile strength and stiffness to native tendon segments (NTSs). The strain at break and suture retention strength of the DBTSs showed much higher than that of the DTSs (p < 0.05). Additionally, the DBTSs showed higher ultimate load than the DTSs when these scaffolds were sutured with NTSs (p < 0.05) through the modified Kessler technique based on a uniaxial tensile test. This study demonstrated that DTSs may be used as a patch for reinforcing tendon repair, while DBTSs may be used as a bridge for reconstructing tendon defects.

Enhancement of tenogenic differentiation of rat tendon-derived stem cells by biglycan.

Biglycan (BGN) has been identified as one of the critical components of the tendon-derived stem cells (TDSCs) niche and may be related to tendon formation. However, so far, no study has demonstrated whether the soluble BGN could induce the tenogenic differentiation of TDSCs in vitro. The aim of this study was to investigate the effect of BGN on the tenogenic differentiation of TDSCs. The proliferation and tenogenic differentiation of TDSCs exposed to different concentrations of BGN (0, 50, 100, and 500 ng/ml) were determined by the live/dead cell staining assay, CCK-8 assay, quantitative real-time polymerase chain reaction (qRT-PCR), and western blot analysis. The BGN signaling pathway of TDSCs (with and without 50 ng/ml of BGN) was determined by western blot analysis and qRT-PCR analysis. At a concentration of 50 ng/ml, BGN increased the expression of the tenogenic markers THBS-4 and TNMD at both the messenger RNA (mRNA) and protein levels. Meanwhile, 50 ng/ml of BGN inhibited the expression of the chondrogenic and osteogenic markers SOX9, ACN, and RUNX2 at both the mRNA and protein levels. Moreover, BGN (50 ng/ml) affected the expression of the components of the extracellular matrix of TDSCs. Additionally, BGN activated the Smad1/5/8 pathway as indicated by an increase in phosphorylation and demonstrated by inhibition experiments. Upregulation in the gene expression of BMP-associated receptors (BMPRII, ActR-IIa, and BMPR-Ib) and Smad pathway components (Smad4 and 8) was observed. Taken together, BGN regulates tenogenic differentiation of TDSCs via BMP7/Smad1/5/8 pathway and this regulation may provide a basic insight into treating tendon injury.

Effects of hydrogen peroxide on biological characteristics and osteoinductivity of decellularized and demineralized bone matrices.

Due to the similar collagen composition and closely physiological relationship with soft connective tissues, demineralized bone matrices (DBMs) were used to repair the injured tendon or ligament. However, the osteoinductivity of DBMs would be a huge barrier of these applications. Hydrogen peroxide (H2 O2 ) has been proved to reduce the osteoinductivity of DBMs. Nevertheless, the biological properties of H2 O2 -treated DBMs have not been evaluated completely, while the potential mechanism of H2 O2 compromising osteoinductivity is also unclear. Hence, the purpose of this study was to characterize the biological properties of H2 O2 -treated DBMs and search for the proof that H2 O2 could compromise osteoinductivity of DBMs. Decellularized and demineralized bone matrices (DCDBMs) were washed by 3% H2 O2 for 12 h to fabricate the H2 O2 -treated DCDBMs (HPTBMs). Similar biological properties including collagen, biomechanics, and biocompatibility were observed between DCDBMs and HPTBMs. The immunohistochemistry staining of bone morphogenetic protein 2 (BMP-2) was negative in HPTBMs. Furthermore, HPTBMs exhibited significantly reduced osteoinductivity both in vitro and in vivo. Taken together, these findings suggest that the BMP-2 in DCDBMs could be the target of H2 O2 . HPTBMs could be expected to be used as a promising scaffold for tissue engineering. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2019.

Systems-Based Interactome Analysis for Hematopoiesis Effect of Angelicae sinensis Radix: Regulated Network of Cell Proliferation towards Hemopoiesis.

OBJECTIVE: To explore the molecular-level mechanism on the hematopoiesis effect of Angelicae sinensis Radix (ASR) with systems-based interactome analysis. METHODS: This systems-based interactome analysis was designed to enforce the workflow of "ASR (herb)→compound→target protein→internal protein actions→ending regulated protein for hematopoiesis". This workflow was deployed with restrictions on regulated proteins expresses in bone marrow and anemia disease and futher validated with experiments. RESULTS: The hematopoiesis mechanism of ASR might be accomplished through regulating pathways of cell proliferation towards hemopoiesis with cross-talking agents of spleen tyrosine kinase (SYK), Janus kinase 2 (JAK2), and interleukin-2-inducible T-cell kinase (ITK). The hematopoietic function of ASR was also validated by colony-forming assay performed on mice bone marrow cells. As a result, SYK, JAK2 and ITK were activated. CONCLUSION: This study provides a new approach to systematically study and predict the therapeutic mechanism for ASR based on interactome analysis towards biological process with experimental validations.

Stem Cell Extracellular Matrix-Modified Decellularized Tendon Slices Facilitate the Migration of Bone Marrow Mesenchymal Stem Cells.

It is highly desirable to develop a novel scaffold that can induce stem cell migration in tendon tissue engineering and regeneration. The objective of this study is to assess the effect of stem cell extracellular matrix-modified decellularized tendon slices (ECM-DTSs) on bone marrow mesenchymal stem cells (BMSCs) migration and explore the possible molecular mechanisms. Native ECM produced by BMSCs and tendon-derived stem cells (TDSCs) was deposited on DTSs, denoted as bECM-DTSs and tECM-DTSs, respectively, and the migration of BMSCs treated with the extracts from ECM-DTSs was studied. Almost all the seeded stem cells were removed from the stem cell-DTS composites, while ECM produced by stem cells completely covered the surface of the DTSs. Significantly higher levels of chemokines, including stromal cell-derived factor-1 (SDF-1) and monocyte chemotactic protein-1 (MCP-1) were released by ECM-DTSs than by bare DTSs (p < 0.05), according to ELISA, and tECM-DTSs exhibited the highest release within 72 h. bECM-DTSs and tECM-DTSs markedly improved BMSCs migration compared to bare DTSs, with tECM-DTSs yielding the best recruitment effects. The ECM-DTSs led to early cytoskeletal changes compared to bare DTSs (p < 0.05). Migration-related gene and protein expression was significantly up-regulated in BMSCs treated with ECM-DTSs via the PI3K/AKT signaling pathway (p < 0.05), indicating that ECM-DTSs could enhance BMSCs migration via the PI3K/AKT signal pathway, and the effect of tECM-DTSs on BMSCs migration is superior to that of bECM-DTSs. This may provide the experimental and theoretical evidence for using stem cell-derived ECM-modified scaffold as a novel approach to recruit stem cells.

Evaluation of Decellularized Bovine Tendon Sheets for Achilles Tendon Defect Reconstruction in a Rabbit Model.

BACKGROUND: Achilles tendon (AT) defects frequently occur in trauma and chronic injuries. Currently, no method can satisfactorily reconstruct the AT with completely restored function. PURPOSE: To evaluate the postoperative outcomes of AT defect reconstruction with decellularized bovine tendon sheets (DBTSs) in a rabbit model. STUDY DESIGN: Controlled laboratory study. METHODS: DBTSs were prepared from bovine tendons after compression, decellularization, antigen extraction, freeze drying, and sterilization. Platelet-rich plasma (PRP) was obtained by differential centrifugation. Sixty-three rabbits were used in this study, and the AT defect model was created bilaterally. All rabbits were divided into 3 groups (n = 21). In the DBTS group and the DBTS + PRP group, 2-cm-long AT was excised and reconstructed by DBTSs or PRP-treated DBTSs. In the control group, the rabbits underwent AT transection, and stumps were sutured. After surgery, all rabbits were assessed by ultrasonography and magnetic resonance imaging and then sacrificed for histological examination and biomechanical testing at 4, 8, or 12 weeks. RESULTS: Gross observations demonstrated the absence of immunologic incompatibility and rejection. Histological examination showed that DBTSs promoted host cell infiltration and new fibrous tissue integration as compared with the control group. In each group, there was an AT-like structure formation and aligned collagen fiber deposition at 12 weeks. Mechanical properties of the reconstructed AT were not significantly different among the 3 groups at 4, 8, and 12 weeks after surgery ( P > .05). Ultrasonography and magnetic resonance imaging results illustrated that the reconstructed AT from each group maintained remodeling, and there was no significant difference in the echogenicity scoring ( P > .05) and percentages of good and excellent ( P > .05) among the 3 groups. CONCLUSION: DBTSs, which retain the native tendon structure and bioactive factors, had the ability to remodel and integrate into the rabbit AT and improve the healing process. CLINICAL RELEVANCE: DBTSs could serve as an effective bioscaffold to reconstruct AT defects.

Analysis on Inpatient Health Expenditures of Renal Cell Carcinoma in a Grade-A Tertiary Hospital in Beijing.

BACKGROUND: Renal cell carcinoma (RCC) is the most common type of malignant renal tumors with a growing incidence in the recent years. This study aimed to investigate the influencing factors and variation trend of hospitalization expenditures among RCC patients in a single-centered hospital in Beijing during 5 consecutive years and to find the major cost items and fluctuation tendency of inpatient medical expenditures. METHODS: The information of medical expenditures among RCC patients in a Grade-A tertiary hospital during the years 2012-2016 was investigated to find the main cost items and changes affecting the medical cost structure. Gray correlation method was adopted in quantitative analysis to analyze the composition of medical expenditures, and the variation of hospitalization expense structure during the five years was studied by analyzing the degree of structural variation. RESULTS: The cost item constitution of the hospitalization expenditures among RCC patients was relatively stable in the sample hospital during the past five years. To be specific, drug costs accounted for the largest proportion of medical expenditures each year, with the highest of 37.81% in 2012, and showed a slowly declining tendency in the coming years. The cost item with the highest correlation degree was drug costs, with the value of 1.0000; followed by the costs of surgeries, 0.8423. Furthermore, drug costs shared the largest proportion (40.95%) of structural variation, followed by the costs of surgeries (18.35%). CONCLUSIONS: Drug costs are the major influencing factors of the hospitalization expenditures among RCC patients. Thus, reasonable control on excessive drugs as well as the standardization of the diagnosis and treatment behaviors is conducive in reducing medical expenditures as well as easing patients' economic burdens. Besides, the positive growth on surgery costs suggests that the labor value of medical staffs has been gradually recognized.

Fabrication and characterization of a decellularized bovine tendon sheet for tendon reconstruction.

Obtaining a performing decellularized tendon scaffold with proper dimensions and adequate availability is highly desirable. However, the combined study of complete decellularization and detailed characterization of native tendon extracellular matrix (ECM) from large animals is still lacking. In the present study, we developed a new decellularization protocol, including physical methods and enzymatic solutions for processing bovine Achilles tendons, and produced a decellularized bovine tendon sheet (DBTS) scaffold for tendon reconstruction. The decellularization effectiveness was demonstrated by DNA quantification and histological qualification. The removal of the alpha-gal epitopes was confirmed by ELISA analysis and immunohistochemical staining. After decellularization, there were no significant alterations of the native tendon extracellular matrix (ECM) properties, including the internal ultrastructure, biochemical compositions such as collagen, glycosaminoglycans (GAGs), basic fibroblast growth factor (bFGF) and transforming growth factor-ß1 (TGF-ß1), fibronectin and decorin, as well as substantial mechanical strength. Furthermore, the DBTS scaffold showed no cytotoxic and promoted the proliferation of NIH-3T3 fibroblasts in vitro. When implanted into rat subcutaneous tissue, the DBTS scaffold displayed excellent histocompatibility in vivo. Our results, while offering a new decellularization protocol for large tendons, can provide a promising biologic scaffold with a combination of mechanical strength and tendon ECM bioactive factors that may have many potential applications in tendon reconstruction. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2299-2311, 2017.