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Huperzia serrate is a known medicinal plant that produces the Lycopodium alkaloid Huperzine A (HupA). It has been used to treat such diseases as contusions, swellings, and pain since the year of 739. Chemical structure analyses show that HupA exists as two stereoisomers, (−)-HupA and (+)-HupA. The review was aimed to summarize the recent literature data about the biological characteristics, natural sources, synthetic origins, and future prospects in order to provide enhanced understanding of the properties of Huperzine A, and to supply a fundamental framework for the future studies of H. serrata. [ABSTRACT FROM AUTHOR]

Compared with numerous encouraging reports of percutaneous kyphoplasty (PKP) in treatment of painful osteoporotic vertebral compression fractures, there have been fewer reports on the role of PKP in the treatment of nonunion of osteoporotic vertebral compression fractures. Even less is known about the use of PKP in treating nonunion of osteoporotic vertebral compression fractures with severe spinal stenosis. We reported an 87-year-old man presented with half a year back pain and numbness of both legs after back sprain 6 months ago. Nonunion of L3 with severe spinal stenosis was recognized in the preoperative films. Bone mineral analysis showed severe osteoporosis with a T-score of −4.7. He refused to receive the decompression surgery. As a result, PKP was introduced to him as an alternative option. The patient experienced complete pain relief after PKP without any complication. Meanwhile, it was an interesting finding that numbness of both legs disappeared. After 12 months follow-up, the patient was asymptomatic. This case illustrated that PKP could be considered as one of the options for nonunion of osteoporotic vertebral compression fractures with severe spinal stenosis. [ABSTRACT FROM AUTHOR]

Neuroblastoma is a neural crest-derived embryonal tumour of the postganglionic sympathetic nervous system and a disease with several different chromosomal gains and losses, which include MYCN-amplified neuroblastoma on chromosome 2, deletions of parts of the chromosomes 1p and 11q, gain of parts of 17q and triploidy. Recently, activating mutations of the ALK (Anaplastic Lymphoma Kinase) RTK (Receptor Tyrosine Kinase) gene have been described in neuroblastoma. A meta-analysis of neuroblastoma cases revealed that ALK mutations (49 of 709 cases) in relation to genomic subtype were most frequently observed in MYCN amplified tumours (8.9%), correlating with a poor clinical outcome. MYCN proteins target proliferation and apoptotic pathways, and have an important role in the progression of neuroblastoma. Here, we show that both wild-type and gain-of-function mutants in ALK are able to stimulate transcription at the MYCN promoter and initiate mRNA transcription of the MYCN gene in both neuronal and neuroblastoma cell lines. Further, this stimulation of MYCN gene transcription and de novo MYCN protein expression is abrogated by specific ALK inhibitors, such as crizotinib (PF-2341066), NVP-TAE684, and by small interfering RNA to ALK resulting in a decrease in proliferation rate. Finally, co-transfection of ALK gain-of-function mutations together with MYCN leads to an increase in transformation potential. Taken together, our results indicate that ALK signalling regulates initiation of transcription of the MYCN gene providing a possible explanation for the poor clinical outcome observed when MYCN is amplified together with activated ALK. [ABSTRACT FROM AUTHOR]

Background: We have previously demonstrated that overexpression of ankyrin repeat-rich membrane spanning (ARMS) protein facilitates melanoma formation via conferring apoptotic resistance. This study aims to investigate whether ARMS contributes to melanoma progression.Method: Using immunohistochemistry, we graded the expression level of ARMS in 54 cases of primary melanoma and 46 cases of metastatic melanoma. The immunointensity of ARMS was statistically correlated with individual clinicopathological characteristics. By RNA interference, stable melanoma cell clones with ARMS-knockdown were constructed, and were used for in vitro scratch wound, transwell invasion assays, and in vivo lung metastasis experiment.Results: Stronger immunointensity of ARMS was observed mostly in melanomas with Breslow tumour thickness >1.0  mm (Fisher's exact test, P=0.002) or with nodal metastasis (Fisher's exact test, P=0.026), and was correlated with a worse overall survival in melanoma patients (log-rank test, P=0.04). Depletion of ARMS inhibited migration, invasion, and metastatic potential of melanoma cells in vitro and in vivo. Moreover, ARMS mediated melanoma cell migration and invasion through activation of the extracellular signal-regulated kinase (ERK) kinase (MEK)/ERK signalling pathway.Conclusion: Ankyrin repeat-rich membrane spanning expression, conjunctly with tumour thickness or ulceration, may serve as a prognostic factor in patients with cutaneous melanoma. [ABSTRACT FROM AUTHOR]

New injectable bone substitutes have been developed that are, unlike polymethylmethacrylate, biologically active and have an osteogenic effect leading to osteogenesis and bone remodeling for vertebroplasty or kyphoplasty. In this study, we developed a sheep vertebral bone defect model to evaluate the new bioactive materials and assessed the feasibility of the model in vivo. Bone voids were experimentally created on lumbar vertebrae L2-L5 with L1 and L6 left intact as a normal control in mature sheep. The defect vertebrae L2-L5 in each sheep were randomized to receive augmentation with calcium phosphate cement (CPC) or sham. Vertebrae (L1-L6) were collected after 2 and 24 weeks of the cement augmentation and their strength and stiffness, as well as osseointegration activity and biodegradability, were evaluated. Finally, CPC significantly improved the strength and stiffness of vertebrae but did not yet restore it to the normal level at 24 weeks. Osteogenesis occurred at a substantially high level after 24 weeks of CPC augmentation or sham. Therefore, the sheep vertebral model with one void, 6.0 mm in diameter and 15.0 mm in depth, is replicable and can be used for evaluating the new injectable bioactive materials in vertebral augmentation or reconstruction. [ABSTRACT FROM AUTHOR]

Many different types of cancer originate from aberrant signaling from the anaplastic lymphoma kinase (ALK) receptor tyrosine kinase (RTK), arising through different translocation events and overexpression. Further, activating point mutations in the ALK domain have been recently reported in neuroblastoma. To characterize signaling in the context of the full-length receptor, we have examined whether ALK is able to activate Rap1 and contribute to differentiation/proliferation processes. We show that ALK activates Rap1 via the Rap1-specific guanine-nucleotide exchange factor C3G, which binds in a constitutive complex with CrkL to activated ALK. The activation of the C3G/Rap1 pathway results in neurite outgrowth of PC12 cells, which is inhibited by either overexpression of Rap1GAP or siRNA-mediated knockdown of Rap1 itself or the guanine nucleotide exchange factor C3G. Significantly, this pathway also appears to function in the regulation of proliferation of neuroblastoma cells such as SK-N-SH and SH-SY5Y, because abrogation of Rap1 activity by Rap1-specific siRNA or overexpression of Rap1GAP reduces cellular growth. These results suggest that ALK activation of Rap1 may contribute to cell proliferation and oncogenesis of neuroblastoma driven by gain-of-function mutant ALK receptors. [ABSTRACT FROM AUTHOR]

Study design:Retrospective study.Objectives:To investigate prognostic factors of sacral chordomas and provide theoretical foundation for an improvement of continuous disease-free survival (CDFS).Methods:Thirty-six patients underwent initial operation for sacral chordoma between 1992 and 2007. Data regarding age, gender, tumor size, tumor location, and type of surgery, surgical margins, surrounding muscle invasion, radiation therapy, and recurrences were reviewed and analyzed statistically.Results:The average duration of follow-up was 74.4 months (range, 16–182 months). Sixteen patients developed local recurrences at the time of final follow-up. The average recurrence time was 30 months (range, 3–84 months). The 5-year and 10-year actuarial CDFS were 59.5 and 42%, respectively. CDFS was found statistically longer in patients whose tumor highest level at or below S3 compared with above S3 (P=0.047). Patients who had invasion into the surrounding muscle had a shorter CDFS than those without surrounding muscle invasion (P=0.014). Statistic analysis showed that the type of surgery was the most valuable indicator of CDFS (P=0.001). The local recurrence rate was statistically higher when an inadequate margin has been achieved (P=0.021). The Cox multivariate regression analysis showed that surrounding muscle invasion (P=0.024) was an independent adverse prognostic factor for CDFS, whereas incomplete excision (P=0.056) achieved borderline significance.Conclusions:The higher level of tumor involvement, invasion into the surrounding muscle, incomplete excision, and inadequate surgical margins are poor prognostic factors. Resecting the tumor completely with wide surgical margins may provide a better prognosis for these patients. [ABSTRACT FROM AUTHOR]

Delay systems used to model retarded actions are relevant in many fields such as optics, mechanical machining, biology or physiology. A frequently encountered situation is that the length of the delay time changes with time. In this study, we use a simple map system to investigate the influence of the fluctuating delay time on the system dynamics. For simplicity, we start from a case with the delay time taking only the value of zero or one discrete time steps, where the system dynamics reduces to one- and two-dimensional map, respectively. We study two situations, periodic or random variation of the delay. Rich dynamics including coexisting multiple attractors, strange nonchaotic attractors and on-off intermittency are observed. For a special case we can show analytically the existence of a dense set of singularities of the Lyapunov exponent. Finally we present results for higher dimensional generalizations to show the relevance of our findings to more general situations. [ABSTRACT FROM AUTHOR]

A novel dmit organometallic complex: [(C2H5)4N]2[Cu(dmit)2] (dmit2-=1,3-dithiole-2-thione-4,5-dithiolate), abbreviated as EtCu, was synthesized. Afterwards its optical nonlinearities in acetone solution at 532 nm and 1064 nm were studied by the Z-scan technique with laser pulses of picosecond duration. The two-photon absorption at 1064 nm and the saturable absorption at 532 nm were observed. The Z-scan curves also revealed that EtCu sample solutions exhibited self-defocusing effects at both wavelengths. The origins were analyzed for the differences between the results. All the outcomes suggest that this material is potential for nonlinear optical device applications. [ABSTRACT FROM AUTHOR]

Supramolecular 2,3- and 2,5-pyridinedicarboxylate (PDC) intercalated ZnAl-layered double hydroxides (2,3- and 2,5-PDC–ZnAl–LDHs) have been prepared by ion exchange method. The structure and composition of the intercalated materials have been studied by X-ray diffraction (XRD) and inductively coupled plasma emission spectroscopy (ICP). The study indicates that the 2,3-PDC and 2,5-PDC anions are accommodated as interdigitated bilayer and monolayer arrangement respectively between the sheets of LDHs. Furthermore, their thermal decomposition processes were studied by the use of in situ high temperature X-ray diffraction (HT-XRD), and the combined technique of thermogravimetry-differential thermal analysis-mass spectrometry (TG-DTA-MS) under N2 atmosphere. Based on the comparison study on the temperatures of both decarboxylation and complete decomposition of interlayer PDC, it can be concluded that 2,5-PDC–ZnAl–LDHs has higher thermal stability than that of 2,3-PDC–ZnAl–LDHs. [ABSTRACT FROM AUTHOR]

Composite thin films of PbTiO3 nanocrystals and PEK-c polymer for applications in nonlinear optical devices were prepared by spin coating. The size of PbTiO3 nanocrystals was estimated to be 30–40 nm. The microstructure of PbTiO3/PEK-c composite polymer film before and after poling was analyzed by X-ray diffraction, which show that this film is c axis-orientated. The poled composite film displayed the refractive index anisotropy. In this sample the TE- and TM-indices differences are found to be 0.02945 for 633 nm and 0.03915 for 414 nm. The electro-optic coefficient γ33 of poled composite film was measured to be 12.89 pm V-1 at 633 nm by the transmission technique. The dielectric constant ε of it at 100 KHz under room temperature was determined to be 7.32. The figure of merit F2 was estimated to be 492. In addition, a relaxation process was observed in the time range of 28 days and the relaxation time constant was calculated to be 2393 min. [ABSTRACT FROM AUTHOR]

OCI-5/Glypican 3, a member of the glypican family of proteoglycans, is the defective gene in the Simpson-Golabi-Behmel overgrowth syndrome. OCI-5 expression is developmentally regulated in the intestinal epithelium, and the mechanism of its regulation was studied in the rat intestinal epithelial cell line IEC-18. A large induction of OCI-5 transcript and protein was observed at high cell density. Among other glypican family members, κ-glypican also exhibited a confluence-dependent induction in select cell types. Nuclear run-on analysis indicated that cell-density regulation of OCI-5 occurs at the level of transcription. The rat and mouse OCI-5 promoters were cloned and found to be highly conserved, located within CpG islands and contain regions of alternating purine and pyrimidine residues. No TATA-box or recognizable INR element was observed. Consensus binding sites for AP-2, SP-1, zeste and NF-1/CTF are conserved across human, mouse and rat promoters. 5′ deletion mapping of the rat promoter identified regions which enhance and repress promoter activity, with no apparent confluence-dependence or tissue-specificity. Nuclear run-on analysis probing different regions of the gene suggests that elongation control plays a role in the induction of OCI-5 by confluence. [ABSTRACT FROM AUTHOR]

Discusses the superplastic deformation of Al-Cu-Mg-Ag alloys at elevated temperatures. Tensile properties of the sample; Observation of high strength and large elongation to failure in the alloys; Effect of the alloy composition on the properties; Elongation to failure and flow stress versus initial strain; Occurrence of maximum elongation failure for the low-copper alloy.

Discusses a simple transmission technique for measuring the electrooptic coefficients of poled polymer films. Principle of the method; Determination of the electrooptic coefficient; Use of the method to characterize nonlinear optical polymers; Reliability of the method.