Biodentine enhances the proliferation and differentiation of osteoblasts through upregulating bone morphogenetic protein-2北大核心

BACKGROUND: Biodentine is a new kind of biocompatible calcium silicate dental restoration material. It can not only increase the secretion of growth factors in dental pulp cells, but also induce the mineralization of dentin. However, the research of Biodentine in bone repair is few. OBJECTIVE: To investigate the effects of Biodentine on the proliferation and differentiation of bone morphogenetic protein-2 interfered mouse osteoblast precursor cell lines by constructing mouse osteoblast precursor cell lines in which bone morphogenetic protein-2 was interfered. METHODS: The 0.1, 1, 10, and 100 g/L Biodentine extract was applied to mouse osteoblast precursor cells for 24 hours. The optimal concentration of 10 g/L was selected by CCK-8 and alkaline phosphatase for the following experiments. Biodentine extract was used to treat mouse osteoblast precursor cells for 1, 3, 5 and 7 days, and the non-intervention group was used as the control group. The cell proliferation and osteogenic differentiation were observed by CCK-8 assay and alkaline phosphatase activity test. Mouse osteoblast precursor cell lines were constructed by interfering with bone morphogenetic protein-2. The proliferation and osteogenic differentiation of cells were observed by CCK-8 assay and alkaline phosphatase activity test. The mouse osteoblast precursor cell lines interfering with bone morphogenetic protein-2 were constructed. The Biodentine group was added with 10 g/L Biodentine extract, and the non-intervention group was set as the control. After 24 and 48 hours of treatment, the proliferation and osteogenic differentiation of the cells were observed by CCK-8 assay and alkaline phosphatase activity test. After 24 hours of treatment, the expression levels of alkaline phosphatase mRNA and protein were detected by real-time PCR and western blot assay. RESULTS AND CONCLUSION: (1) 10 g/L Biodentine extract could promote the proliferation and osteogenic differentiation of mouse osteoblast progenitor cells at 1, 3, 5 and 7 days. (2) Interfering with bone morphogenetic protein-2 could inhibit the proliferation and osteogenic differentiation of mouse osteoblast progenitor cells. (3) The cell proliferation and osteogenic differentiation abilities of Biodentine group were higher than those of control group at 24 and 48 hours (P < 0.05), and the expression levels of alkaline phosphatase mRNA and protein of Biodentine group were higher than those of the control group (P<0.05). (4) The results showed that 10 g/L Biodentine could enhance the proliferation and osteogenic differentiation of osteoblasts through bone morphogenetic protein-2. © 2022, Publishing House of Chinese Journal of Tissue Engineering Research. All rights reserved.     

Repair of rabbit radial bone defects using bone morphogenetic protein-2 combined with 3D porous silk fibroin/β-tricalcium phosphate hybrid scaffolds

Our study aimed to investigate the effect of bone morphogenetic protein-2 (BMP-2) bound to silk fibroin and β-tricalcium phosphate (SF/β-TCP) hybrid on the healing of critical-size radial defects in rabbits. A 15-mm critical-size defect was induced at mid-diaphysis in the left radius of 20 New Zealand white rabbits (average age, 3.5 months; weight, 2.5–3.0 kg). The animals were randomized into Group 1 (SF/β-TCP combined with BMP-2), Group 2 (SF/β-TCP alone), and Group 3 (nothing implanted). Radiographs were obtained every 2 weeks and euthanasia was performed after 8 weeks for visual, radiological, micro-computed tomography (micro-CT), and histological studies. Eight weeks after implantation (SF/β-TCP combined with BMP-2), radiographs showed that new bone formed on the surface of the implant and had bridged the defect in Group 1. Micro-CT imaging also confirmed the formation of new bone around the implant, and the newly formed bone was quantified. Histological examination revealed newly formed bone in the implanted area. Meanwhile, there was no formation of new bone in Group 3. Among the groups, most active formation of new bones was found in Group 1, while there was no difference between Group 2 and Group 3. Based on these results, we concluded that BMP-2-SF/β-TCP showed significant improvement in healing of critical-size defects. Therefore, the combination of BMP-2 and SF/β-TCP would be useful in the field of bone tissue engineering.     

Chitosan–poly(lactide-co-glycolide) microsphere-based scaffolds for bone tissue engineering: In vitro degradation and in vivo bone regeneration studies

Natural polymer chitosan and synthetic polymer poly(lactide-co-glycolide) (PLAGA) have been investigated for a variety of tissue engineering applications. We have previously reported the fabrication and in vitro evaluation of a novel chitosan/PLAGA sintered microsphere scaffold for load-bearing bone tissue engineering applications. In this study, the in vitro degradation characteristics of the chitosan/PLAGA scaffold and the in vivo bone formation capacity of the chitosan/PLAGA-based scaffolds in a rabbit ulnar critical-sized-defect model were investigated. The chitosan/PLAGA scaffold showed slower degradation than the PLAGA scaffold in vitro. Although chitosan/PLAGA scaffold showed a gradual decrease in compressive properties during the 12-week degradation period, the compressive strength and compressive modulus remained in the range of human trabecular bone. Chitosan/PLAGA-based scaffolds were able to guide bone formation in a rabbit ulnar critical-sized-defect model. Microcomputed tomography analysis demonstrated that successful bridging of the critical-sized defect on the sides both adjacent to and away from the radius occurred using chitosan/PLAGA-based scaffolds. Immobilization of heparin and recombinant human bone morphogenetic protein-2 on the chitosan/PLAGA scaffold surface promoted early bone formation as evidenced by complete bridging of the defect along the radius and significantly enhanced mechanical properties when compared to the chitosan/PLAGA scaffold. Furthermore, histological analysis suggested that chitosan/PLAGA-based scaffolds supported normal bone formation via intramembranous formation.     

The architecture of the ipsilateral quadriceps two years after successful anterior cruciate ligament reconstruction with bone–patellar tendon–bone autograft

BackgroundWe undertook a cross-sectional study to evaluate the pennation angle and muscle thickness of the vastus lateralis muscle in patients undergoing unilateral anterior cruciate ligament (ACL) reconstruction with bone–patellar tendon–bone autograft, and compared these values with the contralateral non-operated limb.MethodsTwenty three consecutive athletic males who underwent ACL reconstruction using the central third of the patellar ligament were evaluated at 25.9 ± 1.5 months. The International Knee Documentation Committee (IKDC) score was administered, and angles of pennation and muscle thickness were measured by ultrasonography.ResultsThere was no significant difference in the pennation angle of the operated leg comparing to the contralateral leg (12.5° ± 1.81° in the operated leg; 13.25° ± 2.40° after the test; p = 0.117). Quadriceps thickness in the operated leg was significantly decreased in all subjects compared to the contralateral leg (28.4 ± 5.3 mm in the operated leg; 32.7 ± 4.85 mm in the contralateral leg; p = 0.007).ConclusionsTwo years after surgery, there is no difference in pennation angle of the vastus lateralis when compared to the contralateral side in patients undergoing unilateral ACL reconstruction with bone–patellar tendon–bone autograft. There is a significant difference in quadriceps muscle thickness, which was less in the operated side on the operated side in all patients. Further studies are required to study the influence of muscle architecture on clinical outcome after ACL reconstruction surgery, and whether there are differences associated with the use of different grafts.Level of evidenceCase–control study; level IV.     

Delayed onset muscle soreness at tendon–bone junction and muscle tissue is associated with facilitated referred pain

Delayed onset muscle soreness (DOMS) involves central and peripheral pain mechanisms. Referred pain patterns following stimulation of DOMS affected tissue have not been fully described. Referred pain may provide information on how central mechanisms are involved in DOMS, as referred pain is a central mechanism. Further, tendon tissue involvement in DOMS is not clear. This study assessed pressure pain threshold (PPT) sensitivity at the tendon, tendon–bone junction (TBJ) and muscle belly sites of tibialis anterior pre- and during DOMS in 45 subjects (34 males, 11 females). Furthermore, pain and referred pain areas at these three sites in response to hypertonic saline injection (n = 15 per injection site) were investigated pre- and during DOMS. DOMS was induced using controlled plantarflexion from a platform (bodyweight as resistance) causing eccentric contraction of the tibialis anterior muscle. DOMS induced PPT decrease was found at the TBJ and muscle belly sites only (P < 0.001). No mechanical effect was found in the unexercised limb. Maximal pain intensity induced by hypertonic saline given pre-DOMS was significantly higher for the tendon and TBJ injections compared to intramuscular injections (P < 0.05). Significantly higher referred pain frequency and enlarged pain areas were found at the muscle belly and TBJ sites following injection during DOMS compared to pre-DOMS. The results indicate that muscle belly and TBJ sites are sensitised while tendon tissue per se is unaffected by DOMS. Central sensitivity changes caused by DOMS may explain the increase in referred pain frequency and enlarged pain areas.     

Combination of BMP-2-releasing gelatin/β-TCP sponges with autologous bone marrow for bone regeneration of X-ray-irradiated rabbit ulnar defects

The objective of this study is to evaluate the feasibility of gelatin sponges incorporating β-tricalcium phosphate (β-TCP) granules (gelatin/β-TCP sponges) to enhance bone regeneration at a segmental ulnar defect of rabbits with X-ray irradiation. After X-ray irradiation of the ulnar bone, segmental critical-sized defects of 20-mm length were created, and bone morphogenetic protein-2 (BMP-2)-releasing gelatin/β-TCP sponges with or without autologous bone marrow were applied to the defects to evaluate bone regeneration. Both gelatin/β-TCP sponges containing autologous bone marrow and BMP-2-releasing sponges enhanced bone regeneration at the ulna defect to a significantly greater extent than the empty sponges (control). However, in the X-ray-irradiated bone, the bone regeneration either by autologous bone marrow or BMP-2 was inhibited. When combined with autologous bone marrow, the BMP-2 exhibited significantly high osteoinductivity, irrespective of the X-ray irradiation. The bone mineral content at the ulna defect was similar to that of the intact bone. It is concluded that the combination of bone marrow with the BMP-2-releasing gelatin/β-TCP sponge is a promising technique to induce bone regeneration at segmental bone defects after X-ray irradiation.     

In vitro mineralization and bone osteogenesis in poly(ε-caprolactone)/gelatin nanofibers

The implementation of bio-inspired strategies in developing scaffolds for the reconstruction of oral, craniofacial and bone skeletal tissues after injury or resection remains a challenge. Currently, advanced scaffolds comprising nanofibers endowed with biochemical/biophysical signaling capability offer great advantages in bone regeneration, because of their faithful mimesis of the characteristic size scales encountered in the fibrous network of the native extracellular matrix (ECM). In this study, we investigate the biological potential of nanofibers made of polycaprolactone and gelatin on guiding the regenerative mechanisms of bone. Contact angle measurements and environmental SEM investigations indicate a weak linkage of gelatin molecules to PCL chains, facilitating an efficient adhesion signal to cells up to 3 days of culture. In vitro studies performed on human mesenchymal stem cells (hMSC) until 3 weeks in culture medium with osteogenic supplementation, clearly showing the effectiveness of PCL/Gelatin electrospun scaffolds in promoting bone osteogenesis and mineralization. The increase of alkaline phosphatase activity (ALP) and gene expression of bone-related molecules (bone sialoprotein, osteopontin and osteocalcin), indicated by immunodetection and upregulation level of mRNA, confirm that proposed nanofibers promote the osteogenic differentiation of hMSC, preferentially in osteogenic medium. Moreover, the evidence of newly formed collagen fibers synthesis by SIRCOL and their mineralization evaluated by Alizarin Red staining and EDS mapping of the elements Ca, P and Mg corroborate the idea that native osteoid matrix is ultimately deposited. All these data suggest that PCL and gelatin electrospun nanofibers have great potential as osteogenesis promoting scaffolds for successful application in bone surgery. ? 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:3008-3019, 2012.     

Synthesis and characterization of poly(methyl methacrylate)-based experimental bone cements reinforced with TiO2–SrO nanotubes

In an attempt to overcome existing limitations of experimental bone cements we here demonstrate a simple approach to synthesizing strontium-modified titania nanotubes (n-SrO–TiO₂ tubes) and functionalize them using the bifunctional monomer methacrylic acid. Then, using ‘grafting from’ polymerization with methyl methacrylate, experimental bone cements were produced with excellent mechanical properties, radiopacity and biocompatibility. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive spectroscopy mapping and backscattered SEM micrographs revealed a uniform distribution of SrO throughout the titanium matrix, with retention of the nanotubular morphology. Nanocomposites were then reinforced with 1, 2, 4 and 6 wt.% of the functionalized metal oxide nanotubes. Under the mixing and dispersion regime employed in this study, 2 wt.% appeared optimal, exhibiting a more uniform dispersion and stronger adhesion of the nanotubes in the poly(methyl methacrylate) matrix, as shown by TEM and SEM. Moreover, this optimum loading provided a significant increase in the fracture toughness (K_IC) (20%) and flexural strength (40%) in comparison with the control matrix (unfilled) at P < 0.05. Examination of the fracture surfaces by SEM showed that toughening was provided by the nanotubes interlocking with the acrylic matrix and crack bridging during fracture. On modifying the n-TiO₂ tubes with strontium oxide the nanocomposites exhibited a similar radiopacity to a commercial bone cement (CMW® 1), while exhibiting a significant enhancement of osteoblast cell proliferation (242%) in vitro compared with the control at P < 0.05.     

Bioabsorbable interference screws can be used with less tunnel widening in anatomic rectangular tunnel anterior cruciate ligament reconstruction with a bone–patellar-tendon–bone graft

BackgroundThe purpose of this study was to investigate postoperative tunnel widening after rectangular tunnel bone–patellar-tendon–bone graft anterior cruciate ligament reconstruction using newer-generation bioabsorbable interference screws.MethodsForty-six patients who had undergone primary rectangular tunnel bone–patellar-tendon–bone graft anterior cruciate ligament reconstruction using MILAGRO bioabsorbable interference screws (DePuy Synthes, Warsaw, IN, USA) for femoral fixation and for whom computed tomography was performed at two weeks and one year postoperatively were included in this prospective study. To assess the tunnel widening, the cross-sectional area of the femoral tunnel aperture (compared between two weeks and one year postoperatively) was assessed using computed tomography. Cyst formation, postoperative screw breakage, screw migration, and graft migration were also evaluated using computed tomography one year postoperatively.ResultsMean tunnel widening was 1.9%, and the cross-sectional area of the femoral tunnel aperture was not significantly different between two weeks and one year postoperatively. Postoperative cyst formation, screw breakage, screw migration, and graft migration were not observed in any patient.ConclusionsAfter rectangular tunnel bone–patellar-tendon–bone graft anterior cruciate ligament reconstruction using bioabsorbable interference screws for femoral fixation, tunnel widening was not observed via computed tomography analysis at two weeks and one year postoperatively.     

Aspartic acid-based modified PLGA–PEG nanoparticles for bone targeting: In vitro and in vivo evaluation

Nanoparticles (NP) that target bone tissue were developed using PLGA–PEG (poly(lactic-co-glycolic acid)–polyethylene glycol) diblock copolymers and bone-targeting moieties based on aspartic acid, (Asp)_n(1,3). These NP are expected to enable the transport of hydrophobic drugs. The molecular structures were examined by ¹H NMR or identified using mass spectrometry and Fourier transform infrared (FT-IR) spectra. The NP were prepared using the water miscible solvent displacement method, and their size characteristics were evaluated using transmission electron microscopy (TEM) and dynamic light scattering. The bone targeting potential of the NP was evaluated in vitro using hydroxyapatite affinity assays and in vivo using fluorescent imaging in zebrafish and rats. It was confirmed that the average particle size of the NP was <200 nm and that the dendritic Asp₃ moiety of the PLGA–PEG–Asp₃ NP exhibited the best apatite mineral binding ability. Preliminary findings in vivo bone affinity assays in zebrafish and rats indicated that the PLGA–PEG-ASP₃ NP may display increased bone-targeting efficiency compared with other PLGA–PEG-based NP that lack a dendritic Asp₃ moiety. These NP may act as a delivery system for hydrophobic drugs, warranting further evaluation of the treatment of bone disease.     

Tumor–stromal interactions of the bone microenvironment: in vitro findings and potential in vivo relevance in metastatic lung cancer models

Lung cancer comprises a large variety of histological subtypes with a frequent proclivity to form bone metastasis; a condition associated with dismal prognosis. To identify common mechanisms in the development of osteolytic metastasis, we systematically screened a battery of lung cancer cell lines and developed three models of non-small cell lung cancer (NSCLC) with a common proclivity to form osseous lesions, which represented different histological subtypes. Comparative analysis revealed different incidences and latency times. These differences were correlated with cell-type-specific secretion of osteoclastogenic factors, including macrophage inflammatory protein-1α, interleukin-8 and parathyroid hormone-related protein, some of which were exacerbated in conditions that mimicked tumor–stroma interactions. In addition, a distinct signature of matrix metalloproteinase (MMP) activity derived from reciprocal tumor–stroma interactions was detected for each tumor cell line. Thus, these results suggest subtle differences in the mechanisms of bone colonization for each lung cancer subtype, but share, although each to a different degree, dual MMP and osteoclastogenic activities that are differentially enhanced upon tumor–stromal interactions.     

Electrical Stimulation of the Brain in Wilson–Konovalov Hepatocerebral Dystrophy (a neuromorphological and neurophysiological analysis)

Stereotaxic surgery was performed in 27 patients. Complete elimination of or significant reductions in hyperkinesia were obtained in 17 cases; five patients died. There was no correlation between the severity of clinical manifestations of hepatocellular dystrophy and the relatively normal quantitative measures of cortical and subcortical biopotentials, which were produced on a background of microstructural changes affecting neurons in these regions. It is suggested that qualitative significance of these biopotentials is that they carry an excess pathological spike activity resulting in hyperkinesia. This is supported by the fact that hyperkinesia was suppressed after surgical destruction of the ventrolateral nucleus of the thalamus and subthalamic structures.     

Preparation and preliminary in vitro evaluation of a bFGF-releasing heparin-conjugated poly(ε-caprolactone) membrane for guided bone regeneration

In an effort to improve guided bone regeneration (GBR), we successfully fabricated a novel basic fibroblast growth factor (bFGF)-releasing heparin-conjugated poly(ε-caprolactone) membrane (hep-PCL/bFGF). This material has a porous microstructure with smooth and rough pore walls before and after heparinization, respectively. Our FTIR analyses indicated that chemical bonds were formed between PCL and heparin with a new amide C=O band at 1660 cm^?1 and a band at 3400 cm^?1 that can be attributed to –OH stretching in cross-linked heparin. We showed that bFGF was released from hep-PCL/bFGF in a continuous pattern, which remained for 3 weeks. We evaluated MG63 cell proliferation and biocompatibility of GBR membrane by a CCK-8 assay and a live/dead assay. The CCK-8 results revealed that the hep-PCL/bFGF group had superiority compared to other groups. Furthermore, cell morphology of hep-PCL membrane exhibited larger projected areas than those of PCL surfaces based on scanning electron microscopy analysis and immunofluorescent staining of cell cytoskeleton and vinculin expression. Our alkaline phosphatase activity assay also confirmed better performance of the hep-PCL/bFGF group. These results suggested that this novel hep-PCL/bFGF membrane is suitable for osteoblast-like cells to attach, proliferate, and differentiate. Therefore, the hep-PCL/bFGF membrane has potential to be a biodegradable membrane for GBR and warrants further investigation.     

Mechanical property,biocorrosion and in vitro biocompatibility evaluations of Mg–Li–(Al)–(RE) alloys for future cardiovascular stent application

Mg–Li-based alloys were investigated for future cardiovascular stent application as they possess excellent ductility. However, Mg–Li binary alloys exhibited reduced mechanical strengths due to the presence of lithium. To improve the mechanical strengths of Mg–Li binary alloys, aluminum and rare earth (RE) elements were added to form Mg–Li–Al ternary and Mg–Li–Al–RE quarternary alloys. In the present study, six Mg–Li–(Al)–(RE) alloys were fabricated. Their microstructures, mechanical properties and biocorrosion behavior were evaluated by using optical microscopy, X-ray diffraction, scanning electronic microscopy, tensile tests, immersion tests and electrochemical measurements. Microstructure characterization indicated that grain sizes were moderately refined by the addition of rare earth elements. Tensile testing showed that enhanced mechanical strengths were obtained, while electrochemical and immersion tests showed reduced corrosion resistance caused by intermetallic compounds distributed throughout the magnesium matrix in the rare-earth-containing Mg–Li alloys. Cytotoxicity assays, hemolysis tests as well as platelet adhesion tests were performed to evaluate in vitro biocompatibilities of the Mg–Li-based alloys. The results of cytotoxicity assays clearly showed that the Mg–3.5Li–2Al–2RE, Mg–3.5Li–4Al–2RE and Mg–8.5Li–2Al–2RE alloys suppressed vascular smooth muscle cell proliferation after 5 day incubation, while the Mg–3.5Li, Mg–8.5Li and Mg–8.5Li–1Al alloys were proven to be tolerated. In the case of human umbilical vein endothelial cells, the Mg–Li-based alloys showed no significantly reduced cell viabilities except for the Mg–8.5Li–2Al–2RE alloy, with no obvious differences in cell viability between different culture periods. With the exception of Mg–8.5Li–2Al–2RE, all of the other Mg–Li–(Al)–(RE) alloys exhibited acceptable hemolysis ratios, and no sign of thrombogenicity was found. These in vitro experimental results indicate the potential of Mg–Li–(Al)–(RE) alloys as biomaterials for future cardiovascular stent application and the worthiness of investigating their biodegradation behaviors in vivo.     

HgCl(2)-induced human lymphocyte activation in vitro: a superantigenic mechanism?

Mercuric chloride (HgCl(2)) has been proposed to be a mitogen for human blood lymphocytes in vitro. In our previous study, we demonstrated that HgCl(2) preferentially stimulates the CD4+ T cell subset to blast transformation and DNA synthesis and that the reaction is dependent on CD14+ accessory cells. In order to characterise the responding cells further and to elucidate the mechanism of T cell activation, the T cell receptor (TCR) Vbeta chain expression of the blast-transformed cells was analysed by monoclonal antibodies and flow cytometry. The 22 TCR-Vbeta-specific antibodies used were found to react with 55-80% of the naive CD4+ and CD8+ blood T cells from the different donors. Six to 18% of the lymphocytes, mainly CD4+ T cells, were blast transformed after addition of HgCl(2). The distribution of the lymphoblasts carrying certain TCR Vbeta chains were skewed, and 15-40% expressed the TCR Vbeta2 chain. Furthermore, if cells were pretreated for 5 days with HgCl(2), whereafter recombinant interleukin-2 in fresh medium was added, the TCR Vbeta7+ T cell subset was also stimulated to blast transformation. The superantigen staphyloccal enterotoxin B, as a control, induced blast transformation in 10-26% of the lymphocytes, mainly CD4+ T cells, which were, as expected, positive for Vbeta3, Vbeta12, Vbeta14 or Vbeta17. We conclude that HgCl(2) has characteristics of a superantigen, activating the human lymphocytes in a Vbeta-chain-selective manner in vitro.     

Cytomegalovirus (CMV) seroprevalence in pregnant women, bone marrow donors and adolescents in Germany, 1996–2010

In Germany, studies on the IgG seroprevalence in pregnancy and in women of childbearing age are rare. Therefore, we retrospectively evaluated the CMV IgG seropositive rate in 40,324 pregnant women as well as in 31,093 female and male bone marrow donors over 15 consecutive years (1996-2010). Furthermore, the result of a study conducted in 1999 investigating 1,305 healthy adolescents with known ethnicity was included. The overall CMV IgG seroprevalence in pregnant women (15-50?years) was 42.3%. Age-dependent analysis revealed a significantly higher seropositive rate (55.6%) in young women (15-25?years) than in those aged 26-40?years (37-42%) and in women older than 40?years (48.3%). Over the study period of 15?years, the rate of seroprevalence in pregnant women declined significantly (χ(2) test?相似文献   

Bisphenol A in combination with TNF-α selectively induces Th2 cell-promoting dendritic cells in vitro with an estrogen-like activity

Bisphenol A (BPA) is a monomer used in manufacturing a wide range of chemical products, including epoxy resins and polycarbonate. BPA, an important endocrine disrupting chemical that exerts estrogen-like activities, is detectable at nanomolar levels in human serum worldwide. The pregnancy associated doses of 17β-estradiol (E2) plus tumor-necrosis factor-α (TNF-α) induce distorted maturation of human dendritic cells (DCs) that result in an increased capacity to induce T helper (Th) 2 responses. The current study demonstrated that the presence of BPA during DC maturation influences the function of human DCs, thereby polarizing the subsequent Th response. In the presence of TNF-α, BPA treatment enhanced the expression of CC chemokine ligand 1 (CCL1) in DCs. In addition, DCs exposed to BPA/TNF-α produced higher levels of IL-10 relative to those of IL-12p70 on CD40 ligation, and preferentially induced Th2 deviation. BPA exerts the same effect with E2 at the same dose (0.01–0.1 µΜ) with regard to DC-mediated Th2 polarization. These findings imply that DCs exposed to BPA will provide one of the initial signals driving the development and perpetuation of Th2-dominated immune response in allergic reactions.     

Treatment of a patient with malignant mesothelioma with interferon-α2 based on in vitro sensitivity tests

The case of a 70-year-old patient with an epithelial mesothelioma is presented. The patient suffered from dyspnea due to a right-sided recurrent hemorrhagic effusion. Cytological analysis of the effusion revealed marked lymphocytosis and tumor cells, some of them multinucleated with prominent nucleoli. Open lung biopsy revealed nodular thickening of the diaphragmatic, visceral, and parietal pleura; histological examination of biopsies detected intravascular growth of tumor cells. Immunocytochemical characterization of cultured tumor cells and the biopsy specimens showed positive staining to vimentin and cytokeratin, but negative reaction with antibodies against epithelial membrane associated antigen, leukocyte common antigen, van Willebrand factor, and neurofilament. Hence, the tumor was classified as malignant mesothelioma. In vitro, interferon-2 produced a dose-dependent inhibition of proliferation in the cultured mesothelioma cells. Two weeks after initiation of interferon-2 treatment the patient improved and the pleural effusion vanished. Correspondence to: V Sexl     

Adenovirus-mediated siRNA targeting TNF-α and overexpression of bone morphogenetic protein-2 promotes early osteoblast differentiation on a cell model of Ti particle-induced inflammatory response in vitro

Wear particles are phagocytosed by macrophages and other inflammatory cells, resulting in cellular activation and release of proinflammatory factors, which cause periprosthetic osteolysis and subsequent aseptic loosening, the most common causes of total joint arthroplasty failure. During this pathological process, tumor necrosis factor-alpha (TNF-α) plays an important role in wear-particle-induced osteolysis. In this study, recombination adenovirus (Ad) vectors carrying both target genes [TNF-α small interfering RNA (TNF-α-siRNA) and bone morphogenetic protein 2 (BMP-2)] were synthesized and transfected into RAW264.7 macrophages and pro-osteoblastic MC3T3-E1 cells, respectively. The target gene BMP-2, expressed on pro-osteoblastic MC3T3-E1 cells and silenced by the TNF-α gene on cells, was treated with titanium (Ti) particles that were assessed by real-time PCR and Western blot. We showed that recombinant adenovirus (Ad-siTNFα-BMP-2) can induce osteoblast differentiation when treated with conditioned medium (CM) containing RAW264.7 macrophages challenged with a combination of Ti particles and Ad-siTNFα-BMP-2 (Ti-ad CM) assessed by alkaline phosphatase activity. The receptor activator of nuclear factor-κB ligand was downregulated in pro-osteoblastic MC3T3-E1 cells treated with Ti-ad CM in comparison with conditioned medium of RAW264.7 macrophages challenged with Ti particles (Ti CM). We suggest that Ad-siTNFα-BMP-2 induced osteoblast differentiation and inhibited osteoclastogenesis on a cell model of a Ti particle-induced inflammatory response, which may provide a novel approach for the treatment of periprosthetic osteolysis.     

Middle patellar tendon to posterior cruciate ligament (PT–PCL) and normalized PT–PCL: New magnetic resonance indices for tibial tubercle position in patients with patellar instability

Background

To demonstrate whether the distance between the middle point of the patellar tendon and posterior cruciate ligament (PT–PCL) calculated on a single axial MR image could be an alternative measure to tibial tubercle–PCL (TT–PCL) distance for TT lateralization without the need of imaging processing. To show that normalization of PT–PCL (nPT-PCL) against the maximum diameter of the tibial plateau may help to identify patients with patellar instability (PI).