The Application of Static Magnetic Stimulation Reduces Survival of SH-SY5Y Neuroblastoma Cells.

BACKGROUND/AIM: Central nervous system cancer is still a major public health issue. The effectiveness of treatments is limited and varies depending on the severity of disease. Therefore, there is a demand for the development of novel therapies. Static magnetic stimulation (SMS) emerges as a new therapeutic option. The aim of this study was to evaluate the SMS effects on neuroblastoma cells in culture. MATERIALS AND METHODS: SH-SY5Y neuroblastoma cells were exposed to 0.3T SMS for 6, 12, 24, 36, 72 h, and 6 days. Cell viability (MTT), cell death (annexin-V/PI staining) and cell cycle (DNA content), cell proliferation (CFSE), autophagy (acridine orange), and total mitochondrial mass (MitoTracker™ Red) were analyzed to establish the cellular response to SMS. RESULTS: The viability of SH-SY5Y cells was reduced after exposure to SMS for 24 h and 6 days (p<0.05), without differences for the other times (p>0.05); however, this effect was not related to cell death or cell cycle arrest (p>0.05). In contrast, the viability of human malignant melanoma (HMV-II) cells, used as a tumoral control, was not affected. In addition, stimulated SH-SY5Y cells presented a decrease in mitochondrial mass at both exposure times and a reduction in autophagy and cell proliferation after 6 days (p<0.05). CONCLUSION: SMS application appears to be a promising adjuvant therapy for the treatment of neuroblastoma since it decreases the survival of SH-SY5Y neuroblastoma cells.

Repetitive Transcranial Magnetic Stimulation (rTMS) Reverses the Long-term Memory Impairment and the Decrease of Hippocampal Interleukin-10 Levels, both Induced by Neuropathic Pain in Rats.

Neuropathic pain (NP) is characterized by the presence of spontaneous pain, allodynia and hyperalgesia. Repetitive transcranial magnetic stimulation (rTMS) is one of neuromodulatory techniques that induces satisfactory NP relief, including that from refractory pain patients. The objective of this study was to evaluate rTMS treatment over long term memory (LTM) and hippocampal BDNF and IL-10 levels in rats submitted to a NP model. A total of 81 adult (60-days old) male Wistar rats were randomly allocated to one of the following 9 experimental groups: control, control + sham rTMS, control + rTMS, sham neuropathic pain, sham neuropathic pain + sham rTMS, sham neuropathic pain + rTMS, neuropathic pain (NP), neuropathic pain + sham rTMS and neuropathic pain + rTMS. Fourteen days after the surgery for chronic constriction injury (CCI) of the sciatic nerve, NP establishment was accomplished. Then, rats were treated with daily 5-minute sessions of rTMS for eight consecutive days. LTM was assessed by the object recognition test (ORT) twenty-four hours after the end of rTMS treatment. Biochemical assays (BDNF and IL-10 levels) were performed in hippocampus tissue homogenates. rTMS treatment reversed the reduction of the discrimination index in the ORT and the hippocampal IL-10 levels in NP rats. This result shows that rTMS reverses the impairment LTM and the increase in the hippocampal IL-10 levels, both induced by NP. Moreover, it appears to be a safe non-pharmacological therapeutic tool since it did not alter LTM and neurochemical parameters in naive animals.

Polydimethylsiloxane/nano calcium phosphate composite tracheal stents: Mechanical and physiological properties.

In this study, we report the production and characterization of tracheal stents composed of polydimethylsiloxane/nanostructured calcium phosphate composites obtained by reactive synthesis. Tracheal stents were produced by transfer molding, and in vivo tests were carried out. PDMS was combined with H3 PO4 and Ca(OH)2 via an in situ reaction to obtain nanoparticles of calcium phosphate dispersed within the polymeric matrix. The incorporation of bioactive inorganic substances, such as calcium phosphates, improved biological properties, and the in situ reaction allowed tight coupling of particles to the matrix. Results showed the presence of the nanoparticles of DCPA and CDHA. The porosity generated during mixing decreased the tensile strength and tear properties. Composites presented higher values of cell viability compared with those for PDMS. In vivo tests indicated the presence of inflammatory tissue 30 days after implantation in both cases. Thus, the present biomaterial shows potential for application in tracheal disease, however further evaluation is needed. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2018. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 545-553, 2019.