Approximate Optimization Study of Light Curing Waterborne Polyurethane Materials for the Construction of 3D Printed Cytocompatible Cartilage Scaffolds.

Articular cartilage, which is a white transparent tissue with 1-2 mm thickness, is located in the interface between the two hard bones. The main functions of articular cartilage are stress transmission, absorption, and friction reduction. The cartilage cannot be repaired and regenerated once it has been damaged, and it needs to be replaced by artificial joints. Many approaches, such as artificial joint replacement, hyaluronic acid injection, microfracture surgery and cartilage tissue engineering have been applied in clinical treatment. Basically, some of these approaches are foreign material implantation for joint replacement to reach the goal of pain reduction and mechanism support. This study demonstrated another frontier in the research of cartilage reconstruction by applying regeneration medicine additive manufacturing (3D Printing) and stem cell technology. Light curing materials have been modified and tested to be printable and cytocompatible for stem cells in this research. Design of experiments (DOE) is adapted in this investigation to search for the optimal manufacturing parameter for biocompatible scaffold fabrication and stem cell attachment and growth. Based on the results, an optimal working process of biocompatible and printable scaffolds for cartilage regeneration is reported. We expect this study will facilitate the development of cartilage tissue engineering.

3D Printing of Cytocompatible Water-Based Light-Cured Polyurethane with Hyaluronic Acid for Cartilage Tissue Engineering Applications.

Diseases in articular cartilages have affected millions of people globally. Although the biochemical and cellular composition of articular cartilages is relatively simple, there is a limitation in the self-repair ability of the cartilage. Therefore, developing strategies for cartilage repair is very important. Here, we report on a new liquid resin preparation process of water-based polyurethane based photosensitive materials with hyaluronic acid with application of the materials for 3D printed customized cartilage scaffolds. The scaffold has high cytocompatibility and is one that closely mimics the mechanical properties of articular cartilages. It is suitable for culturing human Wharton's jelly mesenchymal stem cells (hWJMSCs) and the cells in this case showed an excellent chondrogenic differentiation capacity. We consider that the 3D printing hybrid scaffolds may have potential in customized tissue engineering and also facilitate the development of cartilage tissue engineering.

Risk factors for peripheral intravenous catheter infection in hospitalized patients: a prospective study of 3165 patients.

We conducted a prospective study of 6538 polyurethane peripheral intravenous (IV) catheters in 3165 hospitalized adult patients using semiquantitative culture techniques. We found that extending the scheduled catheter replacement interval from 48 to 72 hours to 72 to 96 hours was not a risk factor for local catheter infection, but that catheter insertion by personnel other than IV therapists and the use of continuous infusion to maintain catheter patency were 2 independent risk factors for infection.

NF-kappaB p50 promotes tumor cell invasion through negative regulation of invasion suppressor gene CRMP-1 in human lung adenocarcinoma cells.

Lung adenocarcinoma Cl1-5 cells were selected from parental Cl1-0 cells based on their high metastatic potential. In a previous study, CRMP-1, an invasion suppressor gene, was shown to be suppressed in Cl1-5 cells. However, the regulation of CRMP-1 expression has not been explored. In this study, we showed nuclear factor-kappaB controls CRMP-1 expression. The electromobility shift assay showed that while Cl1-0 cells exhibited low NF-kappaB activity in response to TNF-alpha, an abundance of basal and TNF-alpha-induced NF-kappaB-DNA complex was detected in Cl1-5 cells. Supershift-coupled EMSA and Western blotting of nuclear proteins, however, revealed p50 protein, but not classic p65/p50 heterodimer in the complex. ChIP and EMSA demonstrated that p50 binds to a kappaB site residing between -1753 and -1743 of the CRMP-1 promoter region. Transfection of antisense p50 gene into Cl1-5 cells increased the CRMP-1 protein level and decreased the invasive activity of Cl1-5 cells.

Balance improvement in patients with benign paroxysmal positional vertigo.

OBJECTIVE: To investigate the effect of an additional vestibular stimulated exercise programme on balance for patients with benign paroxysmal positional vertigo. DESIGN: Randomized controlled trial. SETTING: Medical centre. SUBJECTS: Twenty-six subjects with benign paroxysmal positional vertigo involving the unilateral posterior semicircular canal. INTERVENTIONS: Subjects were randomized into experimental or control groups. Thirteen subjects in the experimental group received the canalith repositioning manoeuvre and vestibular stimulated exercise training three times a week for four weeks. Thirteen subjects in the control group received only the canalith repositioning manoeuvre. MAIN MEASURES: Static balance tests, tandem walk test, Dynamic Gait Index and subjective rating of the intensity of vertigo were measured at baseline, two-week and four-week assessments. RESULTS: Compared with the control group, subjects in the experimental group demonstrated a statistically significant improvement in single leg stance with eyes closed at the two-week assessment (P<0.05). Furthermore, stance on foam surface with eyes closed, single-leg stance with eyes closed, and Dynamic Gait Index at the four-week assessment were also significantly improved (P<0.05). CONCLUSION: The present study demonstrated that additional exercise training, which emphasizes vestibular stimulation, can improve balance ability and functional gait performance among patients with benign paroxysmal positional vertigo who had already undergone the canalith repositioning manoeuvre.

Balance ability in patients with benign paroxysmal positional vertigo.

OBJECTIVE: The purpose of the study was to investigate the balance ability of the patients with benign paroxysmal positional vertigo (BPPV). STUDY DESIGN AND SETTING: Twenty-three patients (63.3 +/- 9.2 years of age) with a diagnosis of unilateral posterior semicircular canal BPPV were recruited. Static balance was measured in 4 conditions with eyes open and eyes closed: stance on firm surface, stance on foam surface, left leg stance, and right leg stance. Dynamic balance was measured in tandem walk test. Data of the patients with BPPV were compared to age-matched norm values of the healthy adults. RESULTS: The patients with BPPV demonstrated greater sway velocity in stance on foam surface with eyes closed (P < 0.05), in single leg stance with eyes closed (P < 0.001), and in tandem walk test (P < 0.05) compared to the healthy adults. CONCLUSIONS: Patients with BPPV demonstrated impaired static and dynamic balance ability particularly when depriving visual and changing proprioceptive inputs. SIGNIFICANCE: Clinically, in addition to canalith repositioning maneuver, balance retraining on different conditions may be a useful adjunct to treatment for patients with BPPV.

Glucocorticoid receptor expression in advanced non-small cell lung cancer: clinicopathological correlation and in vitro effect of glucocorticoid on cell growth and chemosensitivity.

The current study aimed to immunohistochemically examine the tumor glucocorticoids receptor (GR) expression in patients with advanced non-small cell lung cancer (NSCLC) and to examine the effect of glucocorticoids (GCs) on the in vitro NSCLC cells growth and chemosensitivity. High GR expression was detected in 51% of the tumor specimens. The difference in tumor GR expression was not associated with cell type, gender, age, or stage. The outcome was significantly superior for patients whose tumor showed high GR expression compared to those with either low expression or non-expression. The median progression-free survival was 8.0 versus 5.6 months (p=0.039) and overall survival was 18.1 versus 10.2 months, (p=0.003), respectively. Almost all these patients have received GC as antiemetics or allergic preventive treatment during chemotherapy courses, therefore, the effect of GC on the chemosensitivity in vivo was not evaluable. However, in vitro cytotoxicity assay showed that dexamethasone (DEX) had heterogeneous effects on the growth and chemosensitivity of the NSCLC cell lines. These findings suggest that tumor samples express high levels of GR in about half of the patients with advanced NSCLC, and this high expression of GR may be associated with better outcome. The effect of GC treatment on the chemosensitivity in NSCLC patients remains to be established.

A pathway for tumor necrosis factor-alpha-induced Bcl10 nuclear translocation. Bcl10 is up-regulated by NF-kappaB and phosphorylated by Akt1 and then complexes with Bcl3 to enter the nucleus.

Bcl10 overexpression and nuclear translocation were originally identified in mucosa-associated lymphoid tissue lymphoma with t(1;14)(p32;q32) chromosome translocation. DNA amplification of Bcl10 was also found in other solid tumors. We have recently shown that nuclear translocation of Bcl10 is a specific molecular determinant of Helicobacter pylori-independent mucosa-associated lymphoid tissue lymphoma (Kuo, S.-H., Chen, L. T., Yeh, K.-H., Wu, M. S., Hsu, H. C., Yeh, P. Y., Mao, T. L., Chen, C. L., Doong, S. L., Lin, J. T., and Cheng, A.-L. (2004) J. Clin. Oncol. 22, 3491-3497). However, the molecular mechanism of Bcl10 nuclear translocation remains unknown. In this study, we observed that tumor necrosis factor-alpha (TNFalpha) up-regulates the expression of Bcl10 and induces a fraction of Bcl10 nuclear translocation in human breast carcinoma MCF7 cells. Chromatin immunoprecipitation assays and electrophoretic mobility shift assays indicated that an NF-kappaB-binding site resides in the Bcl10 5 '-untranslated region. This study also demonstrates that Akt1, activated by TNFalpha, phosphorylates Bcl10 at Ser218 and Ser231 and that phosphorylated Bcl10 subsequently complexes with Bcl3 to enter the nucleus. Either inhibition of Akt1 or depletion of Bcl3 blocks Bcl10 nuclear translocation. In summary, these findings characterize a molecular linkage that directs Bcl10 nuclear translocation in response to TNFalpha treatment.

Skin tumor-promoting potential and systemic effects of pentachlorophenol and its major metabolite tetrachlorohydroquinone in CD-1 Mice.

The mouse skin carcinogenesis model provides a conceptual framework to study the carcinogenesis process. It has been used extensively to assess whether a chemical or physical agent carries a carcinogenic hazard to humans and to define the mechanism involved with the carcinogenic effects. We conducted a study to evaluate whether the tumor-promoting activity of pentachlorophenol (PCP) is mainly from its major metabolite tetrachlorohydroquinone (TCHQ). We applied the mouse skin model to CD-1 mice and the results showed that PCP and TCHQ are much weaker promoters than 12-O-tetradecanoylphorbol-13-acetate (TPA) in mouse skin during a 25-wk experiment. Both PCP and TCHQ could induce mice skin epidermal hyperplasia and proliferating cell nuclear antigen (PCNA) labeling index in the epidermis. However, TCHQ caused a more significant induction of epidermal hyperplasia and PCNA positive cells than PCP. Topical application of PCP, but not TCHQ, induced significant organ enlargement and lymphoma in mice, whereas short-term treatment of TCHQ increased tumor necrosis factor-alpha (TNF-alpha) gene expression in mouse skin. We did not observe a significant association between the carcinogenic process and serum TNF-alpha or interleukin-1 beta (IL-1 beta) levels in mice.