Serous degeneration of bone marrow mimics spinal tumor.

OBJECTIVE: To present a rare case of serous degeneration of bone marrow which resembles primary spinal tumor or bony metastasis to spine. Serous degeneration of bone marrow or gelatinous marrow transformation is a rare disease characterized by focal marrow hypoplasia, fat atrophy, and accumulation of extracellular mucopolysaccharides abundant in hyaluronic acid. Few literature was reviewed and few clinical case was presented. METHODS: Two cases of serous marrow transformation were reported. RESULTS: In the first case, a 29-year-old man suffered from severe left buttock pain. Bone metastasis was impressed in radiology examinations. Percutaneous endoscopic lumbar discectomy was performed along with bone biopsy. In the second case, a 49-year-old man presented lower back pain with radiation to bilateral lower legs. Magnetic resonance imaging revealed a water-like signal lesion in sacrum. Serous marrow transformation was confirmed pathologically in both cases. CONCLUSION: To the best of our knowledge, a case of serous degeneration of bone marrow resembling malignancy has not been reported in the literature. In this report, two cases demonstrate serous transformation of bone marrow mimics spinal tumor.

Optimized decellularization protocol including α-Gal epitope reduction for fabrication of an acellular porcine annulus fibrosus scaffold.

Recent advances in tissue engineering have led to potential new strategies, especially decellularization protocols from natural tissues, for the repair, replacement, and regeneration of intervertebral discs. This study aimed to validate our previously reported method for the decellularization of annulus fibrosus (AF) tissue and to quantify potentially antigenic α-Gal epitopes in the decellularized tissue. Porcine AF tissue was decellularized using different freeze-thaw temperatures, chemical detergents, and incubation times in order to determine the optimal method for cell removal. The integrity of the decellularized material was determined using biochemical and mechanical tests. The α-Gal epitope was quantified before and after decellularization. Decellularization with freeze-thaw in liquid nitrogen, an ionic detergent (0.1% SDS), and a 24 h incubation period yielded the greatest retention of GAG and collagen relative to DNA reduction when tested as single variables. Combined, these optimal decellularization conditions preserved more GAG while removing the same amount of DNA as the conditions used in our previous study. Components and biomechanical properties of the AF matrix were retained. The decellularized AF scaffold exhibited suitable immune-compatibility, as evidenced by successful in vivo remodeling and a decrease in the α-Gal epitope. Our study defined the optimal conditions for decellularization of porcine AF tissues while preserving the biological composition and mechanical properties of the scaffold. Under these conditions, immunocompatibility was evidenced by successful in vivo remodeling and reduction of the α-Gal epitope in the decellularized material. Decellularized AF scaffolds are potential candidates for clinical applications in spinal surgery.

Platelet-Rich Fibrin Facilitates Rabbit Meniscal Repair by Promoting Meniscocytes Proliferation, Migration, and Extracellular Matrix Synthesis.

Although platelet-rich fibrin (PRF) has been used in clinical practice for some time, to date, few studies reveal its role as a bioactive scaffold in facilitating meniscal repair. Here, the positive anabolic effects of PRF on meniscocytes harvested from the primary culture of a rabbit meniscus were revealed. The rabbit meniscocytes were cultured with different concentrations of PRF-conditioned medium, and were evaluated for their ability to stimulate cell migration, proliferation, and extracellular matrix formation. In vivo, meniscal defects were created via an established rabbit animal model and were evaluated by a histology-based four-stage scoring system to validate the treatment outcome three months postoperatively. The in vitro results showed that PRF could induce cellular migration and promote proliferation and meniscocyte extracellular matrix (ECM) synthesis of cultured meniscocytes. In addition, PRF increased the formation and deposition of cartilaginous matrix produced by cultured meniscocytes. Morphological and histological evaluations demonstrated that PRF could facilitate rabbit meniscal repair. The data highlight the potential utility of using PRF in augmenting the healing of meniscal injuries. These advantages would benefit clinical translation, and are a potential new treatment strategy for meniscal repair.

Extracorporeal shockwave therapy improves short-term functional outcomes of shoulder adhesive capsulitis.

BACKGROUND: The treatment of adhesive capsulitis is a dilemma for orthopaedic rehabilitation specialists. In this study, we assessed whether extracorporeal shockwave therapy (ESWT) improves the functional outcome of primary shoulder adhesive capsulitis. METHODS: In this prospective, randomized, controlled, single-blind clinical trial, we enrolled 40 patients with primary adhesive capsulitis to assess whether ESWT can improve the functional outcome of primary adhesive capsulitis better than oral steroid therapy. Patients were allocated to the oral steroid group or ESWT group with randomization. Functional outcome evaluations were performed using the Constant Shoulder Score (CSS) and Oxford Shoulder Score. RESULTS: Both groups showed significant improvement in the Oxford Shoulder Score evaluation throughout the study period. In the ESWT group, the total CSS and range of motion (ROM) parameter of the CSS in the ESWT group showed significant improvement from the fourth week that was better than that in the steroid group; the activities­of­daily living (ADL) parameter of the CSS achieved significance and was better than that in the steroid group at the sixth week. For the steroid group, pain was significantly reduced from baseline to the fourth week of the study; ADL and ROM improved at the fourth to 12th week. For the ESWT group, ADL and ROM improvements were significant from baseline to the sixth week. CONCLUSION: Our results showed that ESWT can be an alternative treatment, at least in the short-term, for primary adhesive capsulitis of the shoulder. In addition, all of the side effects of ESWT were transient and tolerable.

Mechanical stress-induced apoptosis of nucleus pulposus cells: an in vitro and in vivo rat model.

BACKGROUND: Un-physiological loads play an important role in the degenerative process of inter-vertebral discs (IVD). In this study, we used an in vitro and in vivo rat model to investigate the mechanism of nucleus pulposus (NP) cells apoptosis induced by mechanical stress. METHODS: Static compressive load to IVDs of rat tails was used as the in vivo model. For the in vitro model, NP cells were tested under the physiological and un-physiological loading. For histological examination, apoptotic index study, and apoptotic gene expression, we also selected cytokines [bone morphogenetic protein (BMP)-2/7, insulin-like growth factor (IGF)-1, platelet-derived growth factor (PDGF)] to be analyzed. RESULTS: Under mechanical loading, cellular density was significantly decreased, but there was an increase of TUNEL positive cells and apoptosis index. In a dose-dependent manner; the necrosis became apparent in the un-physiologic strain. The selected cytokines (BMP-2/7, IGF-1, PDGF) can significantly reduce the percentage of apoptotic and necrotic cells. CONCLUSIONS: We conclude that the intrinsic (mitochondrial) apoptotic pathway plays an important role in the compressive load-induced apoptosis of NP cells. Combination therapy reducing the mechanical load and selected cytokines (BMP-2/7, IGF-1 and PDGF) may have considerable promise in the treatment of spine disc degeneration.

Centrifugal force induces human ligamentum flavum fibroblasts inflammation through activation of JNK and p38 pathways.

Inflammation has been proposed to be an important causative factor in ligamentum flavum hypertrophy. However, the mechanisms of mechanical load on inflammation of ligamentum flavum remain unclear. In this study, we used an in vitro model of human ligamentum flavum fibroblasts subjected to centrifugal force to elucidate the effects of mechanical load on cultured human ligamentum flavum fibroblasts; we further studied its molecular and biochemical mechanisms. Human ligamentum flavum fibroblasts were obtained from six patients undergoing lumbar spine surgery. Monolayer cultures of human ligamentum flavum fibroblasts were subjected to different magnitudes of centrifugal forces. Cell viability, cell death, biochemical response, and molecular response to centrifugal forces were analyzed. It was found that centrifugal stress significantly suppressed cell viability without inducing cell death. Centrifugal force at 67.1 g/cm(2) for 60 min significantly increases the production of prostaglandin E2 and nitric oxide as well as gene expression of proinflammatory cytokines, including interleukin (IL)-1α, IL-1ß and IL-6, showed that centrifugal force-dependent induction of cyclooxygense-2 and inducible NO synthase required JNK and p38 mitogen-activated protein kinase, but not ERK 1/2 activities. This study suggested that centrifugal force does induce inflammatory responses in human ligamentum flavum fibroblasts. The activation of both JNK and p38 mitogen-activated protein kinase mechanotransduction cascades is a crucial intracellular mechanism that mediates cyclooxygense-2/prostaglandin E2 and inducible NO synthase/nitric oxide production.

The cross-talk between transforming growth factor-beta1 and ultrasound stimulation during mechanotransduction of rat tenocytes.

Ultrasound is an effective noninvasive treatment for various tendinopathies. However, how tenocytes convert ultrasound stimulation into cascades of cellular and molecular events is not well understood. The purpose of this study is to elucidate the signaling pathways of tenocytes during ultrasound stimulation. Primary cultures of tenocytes were harvested from Achilles tendons of Sprague-Dawley rats. The viability and proliferation of tenocytes, their genes expression, and the signaling pathways after ultrasound treatment with or without specific inhibitors were evaluated and analyzed. The results showed that ultrasound treatment (100 mW/cm(2) for 20 min) significantly enhanced matrix metalloproteinase 13 (MMP-13), c-Fos, and c-Jun gene expression, increased JNK and p38, but not extracellular signal-regulated kinase-1/2 (ERK1/2), phosphorylation at 5 min, and sustained up to 60 min. JNK inhibitor and p38 inhibitor, but not ERK1/2 inhibitor, attenuated ultrasound-dependent induction of MMP-13 expression, indicating that the JNK and p38 pathways are required for ultrasound-induced MMP-13 expression in tenocytes. We also found that SB431542 (transforming growth factor-beta (TGF-ß) receptor kinases inhibitor) suppressed ultrasound-induced MMP?13 and c-Fos gene expression, and p38 phosphorylation. This study revealed that ultrasound treatment stimulates tenocytes proliferation and regulates their matrix metabolism through the cross-talk between TGF-ß and ultrasound-induced mitogen-activated protein kinases (MAPKs) signaling pathways.

Effects of low intensity pulsed ultrasound on rat Schwann cells metabolism.

The effects of low intensity pulsed ultrasound to tenocytes and osteocytes are well understood and applied clinically. However, its effects on cultured Schwann cells are still not well elucidated. This study was designed to elucidate the effects of low intensity pulsed ultrasound on cultured Schwann cells and their possible molecular mechanism. Schwann cells were harvested from sciatic nerves of 3-day-old Sprague-Dawley rats. Low intensity pulsed ultrasound stimulator (frequency: 1 MHz, duration: 2 min, duty cycle: 20%, total treatment time: 3 min) was applied to three different culture conditions: regular culture medium containing 0, 5, or 10% fetal bovine serum. The viability, damage, and differentiation of Schwann cells were examined; gene expression was also analyzed. In the presence of 0.3 W/cm(2) pulsed ultrasound stimulation, increases in cell viability and decreases in cell apoptosis were observed in the serum deprivation group; in this culture condition, interleukin-1, tumor necrosis factor-alpha, and protein zero genes expression were downregulated and Desert Hedgehog transcripts gene expression was upregulated. We concluded that intervention with low intensity pulsed ultrasound could promote Schwann cell proliferation, prevent cell death, and keep adequate phenotype presentation for peripheral nerve recovery. The low intensity pulsed ultrasound stimulation to an injured nerve site could be applied as early as possible especially when the microenvironment is almost serum-free to obtain the most benefit.

Injury mechanism affects the stability of suture-button syndesmosis fixation.

BACKGROUND: Ankle syndesmosis injury is a common condition, and the injury mechanism can be sorted into pure syndesmosis injury, Weber-B, and Weber-C type fractures. This study aims to evaluate the treatment outcomes and stability of suture-button fixation for syndesmosis injury with different injury mechanisms. We hypothesized that injury mechanisms would alter the stability of suture-button fixation. METHODS: We retrospectively reviewed 63 patients with ankle syndesmosis injury who underwent surgery with TightRope (Arthrex, Naples, FL, USA) from April 2014 to February 2019. The stability of suture-button fixation with TightRope was evaluated by comparing the preoperative, postoperative, and final follow-up measurements of tibiofibular clear space (TFCS), tibiofibular overlap (TFO), and medial clear space (MCS). A subgroup analysis for each demographic group and injury type including pure syndesmosis injury, Weber-B, and Weber-C type fractures were performed. RESULTS: Syndesmosis was effectively reduced using TightRope. After the index surgery, the tibiofibular clear space was reduced from 7.73 to 4.04 mm, the tibiofibular overlap was increased from 3.05 to 6.44 mm, and the medial clear space was reduced from 8.12 to 3.54 mm. However, syndesmosis widening was noted at the final follow-up, especially in Weber-C type fractures (TFCS 3.82 to 4.45 mm, p < 0.01 and TFO 6.86 to 6.29 mm, p = 0.04). Though widened, the final follow-up values of tibiofibular clear space and tibiofibular overlap were in the acceptable range. Postoperatively and at the final follow-up, medial clear space was found to be significantly larger in the Weber-C group than in the pure syndesmosis and Weber-B groups (p < 0.05). CONCLUSIONS: Suture-button fixation can offer anatomic reduction and dynamic fixation in syndesmosis injuries. However, when using this modality for Weber-C type fractures, more attention should be focused on the accuracy of reduction, especially of medial clear space, and rediastasis should be carefully monitored. TRIAL REGISTRATION: This trial was retrospectively approved by TMU-JIRB. Registration number N202004122, and the date of approval was May 06, 2020. LEVEL OF EVIDENCE: III.

Augmentation of Tendon Graft-Bone Tunnel Interface Healing by Use of Bioactive Platelet-Rich Fibrin Scaffolds.

BACKGROUND: Platelet-rich fibrin (PRF) is a bioactive biomaterial wherein cytokines are enmeshed within the interconnecting fibrin network. PRF can be fabricated into a patch to augment healing of the interface between a tendon graft and bone tunnel. HYPOTHESIS: The bioactivity of a PRF scaffold is preserved after PRF is mechanically compressed into a patch. A bioactive PRF patch could promote the incorporation of a tendon graft within the bone tunnel through the formation of a tendon-bone healing zone composed of both fibrocartilaginous tissue and new bone. STUDY DESIGN: Controlled laboratory study. METHODS: Bioactivity of PRF was evaluated through treatment of rabbit tenocytes with PRF-conditioned medium and cultivation of cells on a PRF patch. Cellular morphologic features, viability, and differentiation were analyzed accordingly. In an animal study, a rabbit tendon-bone healing model was established through use of New Zealand White rabbits. The implanted tendon graft was enveloped circumferentially with a bioactive PRF patch before being pulled through a bone tunnel in the proximal tibia. Micro-computed tomography (micro-CT) imaging and histological and biomechanical analyses of the tendon-bone interface were performed at 12 weeks postoperatively. RESULTS: PRF improved the viability of the cultured tenocytes. The effects of PRF on in vitro mineralization of tenocytes were comparable with the effects of standard culture medium. The gene expressions of type I collagen and osteopontin were upregulated upon PRF treatment. For the in vivo study, micro-CT images revealed significant new bone synthesis at the tendon-bone interface in the PRF-enveloped group. The tendon-bone healing zone was characterized by abundant fibrocartilage tissue and new bone formation as demonstrated by histological analysis. Biomechanical testing showed significantly higher ultimate loads in the PRF-enveloped group. CONCLUSION: Bioactive PRF could effectively augment healing of tendon graft to bone by inducing the formation of a transitional tendon-bone healing zone composed of fibrocartilage and bone. CLINICAL RELEVANCE: Complete healing of the tendon graft in the bone tunnel is a prerequisite for successful ligament reconstruction, which would allow early and aggressive rehabilitation and rapid return to preinjury activity level. From a translational standpoint, the PRF-augmented healing in this rabbit animal model showed a promising biological approach to enhance tendon graft to bone healing via promotion of the functional anchorage between the 2 different materials.

Concentrated stress effects of contoured and non-contoured high Tibial osteotomy plates: A finite-element study.

BACKGROUND: The TomoFix plate has been extensively used in high tibial osteotomy surgery to stabilize the distracted tibial bones. However, distal pain related to plate irritation was considered one of the most relevant complications for this fixation device. This study aimed to correlate reports of distal pain with the profiles of the distracted tibia and initial plate and plate contour. METHODS: This study used the finite-element method to investigate the profile-, distraction-, and contour-induced effects on stress distribution of the distal tibia-plate contact. The associations of two tibia profiles (normal and concave), distraction angles, and two plate profiles (contoured and non-contoured) were discussed in this study. The areas and stresses of the distal tibia-plate contact were chosen as comparison indices. FINDINGS: Before weight-bearing, the non-contoured plates of the normal and concave tibia profiles consistently showed less contact area at the distal tibia-plate region. Consequently, the physiological loads make the non-contoured plate subject to more concentrated bone stresses and thus may induce more pain at the distal tibia-plate region than a contoured plate. When the distraction angle decreases, the tibia-plate gap increases. Prior to fixation, the tibia-plate gap can be evaluated by the profiles of the distracted tibia and non-contoured plate by use of anteroposterior radiograph and computer-aided simulation. INTERPRETATION: In the situations of a lower distraction angle or a large tibia-plate gap, the use of a plate bender or a lag screw is recommended in order to contour the plate for reducing the concentrated stress at the distal tibia-plate region.

Anti-Inflammatory Effects of Adenine Enhance Osteogenesis in the Osteoblast-Like MG-63 Cells.

BACKGROUND: Adenine is a purine with a role in cellular respiration and protein synthesis. It is considered for its pharmacological potential. We investigated whether anti-inflammatory effect of adenine benefits on the proliferation and maturation of osteoblastic cells. METHODS: Human osteoblast-like cells (MG-63) were cultured with adenine under control conditions or pre-treated with 10ng/mL of tumor necrosis factor-α (TNF-α) followed by adenine treatment. Cell viability was examined using dimethylthiazol diphenyltetrazolium bromide (MTT) assay. Expression of cytokines and osteogenic markers were analyzed using quantitative PCR (qPCR) and ELISA. Enzyme activity of alkaline phosphatase (ALP) and collagen content were measured. RESULTS: TNF-α exposure led to a decreased viability of osteoblastic cells. Treatment with adenine suppressed TNF-α-induced elevation in IL-6 expression and nitrite oxide production in MG-63 cells. Adenine induced the osteoblast differentiation with increased transcript levels of collage and increased ALP enzyme activity. CONCLUSIONS: Adenine exerts anti-inflammatory activity in an inflammatory cell model. Adenine benefits osteoblast differentiation in normal and inflammatory experimental settings. Adenine has a potential for the use to treat inflammatory bone condition such as osteoporosis.

Thermosensitive Chitosan-Gelatin-Glycerol Phosphate Hydrogels as Collagenase Carrier for Tendon-Bone Healing in a Rabbit Model.

Healing of an anterior cruciate ligament graft in bone tunnel yields weaker fibrous scar tissue, which may prolong an already prolonged healing process within the tendon-bone interface. In this study, gelatin molecules were added to thermosensitive chitosan/ß-glycerol phosphate disodium salt hydrogels to form chitosan/gelatin/ß-glycerol phosphate (C/G/GP) hydrogels, which were applied to 0.1 mg/mL collagenase carrier in the tendon-bone junction. New Zealand white rabbit's long digital extensor tendon was detached and translated into a 2.5-mm diameter tibial plateau tunnel. Thirty-six rabbits underwent bilateral surgery and hydrogel injection treatment with and without collagenase. Histological analyses revealed early healing and more bone formation at the tendon-bone interface after collagenase partial digestion. The area of metachromasia significantly increased in both 4-week and 8-week groups after collagenase treatment (p < 0.01). Micro computed tomography showed a significant increase in total bone volume and bone volume/tissue volume in the 8 weeks after collagenase treatment, compared with the control group. Load-to-failure was significantly higher in the treated group at 8 weeks (23.8 ± 8.13 N vs 14.3 ± 3.9 N; p = 0.008). Treatment with collagenase digestion resulted in a 66% increase in pull-out strength. In conclusion, injection of C/G/GP hydrogel with collagenase improves tendon-to-bone healing in a rabbit model.

Functional network reconstruction reveals somatic stemness genetic maps and dedifferentiation-like transcriptome reprogramming induced by GATA2.

Somatic stem cell transplantation holds great promise in regenerative medicine. The best-characterized adult stem cells are mesenchymal stem cells (MSCs), neural stem cells (NSCs), and CD133(+) hematopoietic stem cells (HSCs). The applications of HSCs are hampered since these cells are difficult to maintain in an undifferentiated state in vitro. Understanding genes responsible for stem cell properties and their interactions will help on this issue. The construction of stem cell genetic networks will also help to develop rational strategies to revert somatic cells back to a stem-like state. We performed a systemic study on human CD133(+) HSCs, NSCs, MSCs, and embryonic stem cells and two different progenies of CD133(+) HSCs, microvascular endothelial cells (MVECs) and peripheral blood mononuclear cells. Genes abundant in each or in all three somatic stem cells were identified. We also observed complex genetic networks functioning in postnatal stem cells, in which several genes, such as PTPN11 and DHFR, acted as hubs to maintain the stability and connectivity of the whole genetic network. Eighty-seven HSC genes, including ANGPT1 and GATA2, were independently identified by comparing CD34(+)CD33(-)CD38(-) hematopoietic stem cells with CD34(+) precursors and various matured progenies. Introducing GATA2 into MVECs resulted in dedifferentiation-like transcriptome reprogramming, with HSC genes (such as ANGPT1) being up and endothelial genes (such as EPHB2) being down. This study provides a foundation for a more detailed understanding of human somatic stem cells. Expressing the newly discovered stem cell genes in matured cells might lead to a global reversion of somatic transcriptome to a stem-like status.

Vitamin-D binding protein does not enhance healing in rat bone defects: a pilot study.

Vitamin D-binding protein (DBP) has an anabolic effect on the skeleton and reportedly enhances bone ingrowth. We used an in vivo critical bone defect model to determine whether local administration of DBP promotes bone defect healing. We created a 5-mm segmental bone defect in the radial shaft in a rat model. Forty-eight rats were assigned to eight groups: local application of 1 microg, 5 microg, 10 microg, or 50 microg DBP (DBP-1, DBP-5, DBP-10, DBP-50), autogenous bone marrow mononuclear cells with or without 10 microg DBP (BM-DBP-10, BM), 80 microg BMP-2 delivered in gelatin sponge (BMP-2), and the sham operated group. Radiographic evaluation, histological stains, and epifluorescence microscopy were performed. Grossly, all bone gaps of the BMP-2 group were solidly bridged by callus, while all those in the sham operated group remained unhealed by 9 weeks. Only one specimen of the BM-DBP-10 and DBP-50 groups and three specimens of the BM group were solidly healed; pseudarthroses occurred in all of the other specimens. Histological study and radiographs of the specimens showed similar results. We did not observe the enhanced bone healing reported in a previous study.

Monostotic Vertebral Paget's Disease of the Lumbar Spine.

Paget's disease in the Far East is quite rare. Age at diagnosis is usually greater than 50 years, and the disease typically affects the spine. Most patients are usually diagnosed with Paget's disease following radiographic examination for other purposes. It usually occurs at multiple vertebral levels, with only 10-25% of vertebral Paget's disease being monostotic. The disease rarely causes neurologic complications resulting from compression of intraspinal nerve tissue. Here, we present 2 cases of monostotic vertebral Paget's disease of the third lumbar vertebra. The first patient, who may be the first documented case of Paget's disease in the lumbar spine with progressive neurologic deficiency in an Asian population, received decompressive laminectomy due to marked spinal stenosis with neurologic deficits. The symptoms were greatly relieved following surgery, and ambulatory ability was restored. The second patient was diagnosed with Paget's disease following surgical biopsy. He remained asymptomatic at the most recent follow-up.

Neuroprotective Effect of Schisandra Chinensis on Methyl-4-Phenyl-1,2,3,6-Tetrahydropyridine-Induced Parkinsonian Syndrome in C57BL/6 Mice.

Schisandra chinensis (Turcz.) Baill. (S. chinensis) is a well-known botanical medicine and nutritional supplement that has been shown to have potential effects on neurodegeneration. To investigate the potential neuroprotective effect of S. chinensis fruit extract, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was used to induce behavioral disorders and dopaminergic neuronal damage in mice, and biochemical indicators were examined. Male C57BL/6 mice were used to establish the MPTP-induced parkinsonian syndrome model. Open field and rotarod tests were performed to evaluate the overall manifestation of motor deficits and rodent motor coordination. The mice were divided into 8 groups as follows: normal control; MPTP alone (25 mg/kg, i.p.); S. chinensis extract pretreatment (0.5, 1.5, 5 g/kg, p.o.); and S. chinensis extract treatment (0.5, 1.5, 5 g/kg, p.o.). Liquid chromatography coupled to electrochemical detection was used to monitor neurochemicals in the striatum. Tyrosine hydroxylase content was measured by immunohistochemistry, and biochemical antioxidative indicators were used to evaluate the potential neuroprotective effects of S. chinensis fruit extract. The results demonstrated that treatment with S. chinensis fruit extract ameliorated MPTP-induced deficits in behavior, exercise balance, dopamine level, dopaminergic neurons, and tyrosine hydroxylase-positive cells in the striatum of mice. Among the pretreated and treatment groups, a high dose of S. chinensis fruit extract was the most effective treatment. In conclusion, S. chinensis fruit extract is a potential herbal drug candidate for the amelioration and prevention of Parkinson's disease.

Effects of shock waves on tenocyte proliferation and extracellular matrix metabolism.

The shock wave is an effective noninvasive modality for resolving various tendon pathologies. However, scientific rationale and mechanism of shock wave therapy remains limited. This study aims to investigate the effects of shock waves and their biochemical mechanisms on tenocyte proliferation and collagen synthesis. Tenocytes harvested from Achilles tendons of Sprague-Dawley rats were used in this study. Cell viability was assayed by trypan blue exclusion methods. The colorimetric assay was determined to evaluate the mitochondria activity of the tenocytes after shock wave exposure. Synthesis of collagen, nitric oxide (NO) and transforming growth factor-beta1 (TGF-beta1) were determined and their gene expression was also studied. The results showed that there was a dose-dependent impairment of cell viability observed in 0.36 mJ/mm2 and 0.68 mJ/mm2 stimulation. In the proliferation assay, low energy level with low impulses (0.36 mJ/mm2 with 50 and 100 impulses) showed positive stimulatory effects, whereas the high energy level with high impulses (0.68 mJ/mm2 with 250 and 500 impulses) had significant inhibitory effects. At 0.36 mJ/mm2, 100 impulse shock waves treatment, up-regulation of proliferating cell nuclear antigen (PCNA) (at 6 and 24 h) and collagen type I, collagen type III and TGF-beta1 gene expression (at 24 h) were observed; these were followed by the increases in NO production (at 24 h), TGF-beta1 release (at 48 and 96 h) and collagen synthesis (at the 7th day). This study revealed that shock waves can stimulate tenocyte proliferation and collagen synthesis. The associated tenocyte proliferation is mediated by early up-regulation of PCNA and TGF-beta1 gene expression, endogenous NO release and synthesis and TGF-beta1 protein and then collagen synthesis.

Studies of photokilling of bacteria using titanium dioxide nanoparticles.

Metal pins used to apply skeletal traction or external fixation devices protruding through skin are susceptible to the increased incidence of pin site infection. In this work, we tried to establish the photokilling effects of titanium dioxide (TiO2) nanoparticles on an orthopedic implant with an in vitro study. In these photocatalytic experiments, aqueous TiO2 was added to the tested microorganism. The time effect of TiO2 photoactivation was evaluated, and the loss of viability of five different bacteria suspensions (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus hirae, and Bacteroides fragilis) was examined by the viable count procedure. The bactericidal effect of TiO2 nanoparticle-coated metal plates was also tested. The ultraviolet (UV) dosage used in this experiment did not affect the viability of bacteria, and all bacteria survived well in the absence of TiO2 nanoparticles. The survival curve of microorganisms in the presence of TiO2 nanoparticles showed that nearly complete killing was achieved after 50 min of UV illumination. The formation of bacterial colonies above the TiO2 nanoparticle-coated metal plates also decreased significantly. In this study, we clearly demonstrated the bactericidal effects of titanium dioxide nanoparticles. In the presence of UV light, the titanium dioxide nanoparticles can be applicable to medical facilities where the potential for infection should be controlled.

Ex vivo magnetofection with magnetic nanoparticles: a novel platform for nonviral tissue engineering.

Several methods have been described to introduce DNA expression vectors into mammalian cells both in vitro and in vivo. Each system has benefits and limitations, and to date there is still no ideal method for gene transfer. In this study, we introduced a novel method of gene transfer by using Fe3O4 nanoparticles. The magnetic nanoparticles composed of Fe3O4, and the transfected genes used are Lac Z and enhanced green fluorescence protein gene (EGFG). Four different groups of preparations included in this study were homemade liposome-enveloped EGFP-DNA/Fe3O4, homemade liposome EGFP-DNA gene without magnetic Fe3O4 nanoparticles, lipofectamine 2000-enveloped EGFP-DNA, and EGFP-DNA gene only. Mice osteoblast and He99 lung cancer cell line were used as host cells for gene transfection. The time-dependent EGFP gene expression was monitored and analyzed. The results showed that the diameter of the complex was less than 100 nm. There was no cytotoxicity observed at any of the magnetic Fe3O4 nanoparticle concentrations tested. In the presence of magnetic field, the liposome-enveloped EGFP-DNA/Fe3O4 complex exhibited a much higher efficiency for transfecting EGFP-DNA into osteoblast cells under external magnetic fields. The gene can be transfected into cells with an aid of magnetic vectors and magnetic force. Under a gradient magnetic field, the efficiency of magnetofection is enhanced as compared to that without magnetic field.