Search

Objective: In order to clarify the heat release behavior of neophytadiene under different conditions. Methods: Use Soxhlet extraction method, chromatography column method to extract and purify neophytadiene in tobacco powder, combined with IR, 1H NMR and MS spectrum technology, the structure was confirmed, and Py-GC/MS was used to analyze and study the pyrolysis products of neophytadiene under different conditions. Results: The performance of neophytadiene at different temperatures under anaerobic and aerobic conditions had good cracking thermal stability, and it can still maintain its original state at high temperature. The types of new phytadiene cracking products increased with the increasing of temperature. Under anaerobic conditions, the anaerobic cracking products of cracking products mainly include alkanes and alkenes. In addition to alkanes and alkenes, the main products of cracking under aerobic conditions also produce a large amount of alcohols, aldehydes, ketones, esters, benzene series, and other compounds. Under aerobic conditions, the neo phytadienes were cracked Alcohols, aldehydes, ketones, esters, furans and other compounds containing oxygen atoms, these components have a positive effect on improving the smoking quality of cigarettes. The formation of cracked products mainly comes from primary and secondary reactions The primary reaction of neophytadiene is mainly the scission of α and β bonds of conjugated double bonds, and the secondary reaction is relatively complicated. Conclusion: Neophytadiene has a positive effect on improving the smoking quality of cigarettes.

Aims To study the contribution of epidermal growth factor receptor variant III ( EGFRv III) to glioblastoma multiforme ( GBM) stemness and gefitinib resistance. Methods CD133+ and CD133− cells were separated from EGFRv III+ clinical specimens of three patients with newly diagnosed GBM. Then, RT- PCR was performed to evaluate EGFRv III and EGFR expression in CD133+ and CD133− cells. The tumorigenicity and stemness of CD133+ cells was verified by intracranial implantation of 5 × 103 cells into immunodeficient NOD/ SCID mice. Finally, cells were evaluated for their sensitivity to EGFR tyrosine kinase inhibition by gefitinib. Results RT- PCR results showed that the sorted CD133+ cells expressed EGFRv III exclusively, while the CD133− cells expressed both EGFRv III and EGFR. At 6-8 weeks postimplantation, CD133+/ EGFRv III+/ EGFR− cells formed intracranial tumors. Cell counting kit-8 results showed that the IC50 values of the three isolated EGFRv III+ cell lines treated with gefitinib were 14.44, 16.00, and 14.66 μM, respectively, whereas the IC50 value of an isolated EGFRv III− cell line was 8.57 μM. Conclusions EGFRv III contributes to the stemness of cancer stem cells through coexpression with CD133 in GBMs. Furthermore, CD133+/ EGFRv III+/ EGFR− cells have the ability to initiate tumor formation and may contribute to gefitinib resistance. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a neurodegenerative disorder characterized by progressive loss of dopaminergic (DAergic) neurons and low level of dopamine (DA) in the midbrain. Recent studies suggested that some natural products can protect neurons against injury, but their role on neurotransmitter release and the underlying mechanisms remained unknown. In this work, nanoelectrode electrochemistry was used for the first time to quantify DA release inside single DAergic synapses. Our results unambiguously demonstrated that harpagide, a natural product, effectively enhances synaptic DA release and restores DA release at normal levels from injured neurons in PD model. These important protective and curative effects are shown to result from the fact that harpagide efficiently inhibits the phosphorylation and aggregation of α-synuclein by alleviating the intracellular reactive oxygen level, being beneficial for vesicle loading and recycling. This establishes that harpagide offers promising avenues for preventive or therapeutic interventions against PD and other neurodegenerative disorders., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Object: The authors retrospectively analyzed the surgical treatment of adult intrinsic pontine gliomas in their department, and to enhance the understanding of technical strategies to treat this disease., Methods: 7 patients with intrinsic pontine gliomas were recruited for this study, between January 2011 and June 2013. All patients underwent preoperative MRI and Diffusion Tensor Imaging Fiber Tracking (DTI-FT). In addition, multimodal Intraoperative Neuromonitoring (IOM) and Intraoperative Neuronavigation were also applied during microsurgery., Results: 7 patients with intrinsic pontine gliomas were treated at the West China Hospital of Sichuan University. Mean age, mean duration of symptoms prior to diagnosis, and mean duration of follow-up average time were 38.0 years, 2.0 months, and 23.4 months, respectively. The main presentations were progressive cranial nerve deficits and long tract signs. Total resection was achieved in 3 patients, subtotal resection in 2, and partial resection in 2. Postoperative pathological examination revealed: astrocytoma (WHO II) in 4 cases, anaplastic oligoastrocytoma (AO, WHO III) in one case, and anaplastic astrocytoma (AA, WHO III) in two cases. Postoperative radiotherapy were administered to all patients, and 4 patients with astrocytoma (WHO II) rejected chemotherapy. After 11-39 months of follow-up, patient symptoms were resolved or stable without aggravation except one patient died because of rapidly progressive glioma at 11 months after operation. MRI in other patients showed residual tumor size to be unchanged or without obviously recurrence., Conclusion: Combining preoperative MRI with preoperative DTI-FT, surgery can be better assessed and the operation for adult intrinsic pontine gliomas can be maximally and safely resected with the aid of Multimodal IOMs and Intraoperative Navigation during microsurgery.

Aims: To study the contribution of epidermal growth factor receptor variant III (EGFRvIII) to glioblastoma multiforme (GBM) stemness and gefitinib resistance., Methods: CD133(+) and CD133(-) cells were separated from EGFRvIII(+) clinical specimens of three patients with newly diagnosed GBM. Then, RT-PCR was performed to evaluate EGFRvIII and EGFR expression in CD133(+) and CD133(-) cells. The tumorigenicity and stemness of CD133(+) cells was verified by intracranial implantation of 5 × 10(3) cells into immunodeficient NOD/SCID mice. Finally, cells were evaluated for their sensitivity to EGFR tyrosine kinase inhibition by gefitinib., Results: RT-PCR results showed that the sorted CD133(+) cells expressed EGFRvIII exclusively, while the CD133(-) cells expressed both EGFRvIII and EGFR. At 6-8 weeks postimplantation, CD133(+) /EGFRvIII(+) /EGFR(-) cells formed intracranial tumors. Cell counting kit-8 results showed that the IC50 values of the three isolated EGFRvIII(+) cell lines treated with gefitinib were 14.44, 16.00, and 14.66 μM, respectively, whereas the IC50 value of an isolated EGFRvIII(-) cell line was 8.57 μM., Conclusions: EGFRvIII contributes to the stemness of cancer stem cells through coexpression with CD133 in GBMs. Furthermore, CD133(+) /EGFRvIII(+) /EGFR(-) cells have the ability to initiate tumor formation and may contribute to gefitinib resistance., (© 2013 John Wiley & Sons Ltd.)