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Transcranial magnetic stimulation (TMS) is a non-invasive technique for diagnosis and treatment of various neurological conditions. However, the lack of realistic physical models to test the safety and efficacy of stimulation from magnetic fields generated by the coils has hindered the development of new TMS treatment and diagnosis protocols for several neurological conditions. We have developed an anatomically and geometrically accurate brain and head phantom with an adjustable electrical conductivity matching the average conductivity of white matter and grey matter of the human brain and the cerebrospinal fluid. The process of producing the phantom starts with segmenting the MRI images of the brain and then creating shells from the segmented and reconstructed model ready for 3-D printing and serving as a mold for the conductive polymer. Furthermore, we present SEM images and conductivity measurements of the conductive polymer composite as well as confirmation of the anatomical accuracy of the phantom with computed tomography (CT) images. Finally, we show the results of induced voltage measurements obtained from TMS on the brain phantom.A novel thioether-terminated triazole bridge-containing covalent organic framework (TCOF) was constructed via a simple click chemistry between alkyne and azide monomers for dual-sensitive [pH and glutathione (GSH)] anticancer drug delivery systems. The synthesized TCOFs were crystalline in nature with a pore size of approximately 10-30 nm, as confirmed by powder X-ray diffraction spectroscopy and Brunauer-Emmett-Teller technique. Owing to the flexible nature of the synthesized COF, polyethylene glycol (PEG) modification was easily performed to yield a stable TCOF (TCOF-PEG) colloidal solution. Doxorubicin (DOX)-loaded TCOF-PEG (TCOF-DOX-PEG) exhibited sensitivity to lysosomal pH 5 and GSH environments. DOX release was four times higher under GSH environment (relative to pH 7.4) and three times higher under pH 5 condition because of the dynamic nature of triazole. In contrast, DOX-loaded COF without the triazole ring (I-COF) did not show any significant drug release in pH 7.4 and acidic pH; however, drug release was observed in GSH environment. MTT drug internalization data demonstrated sustained release of DOX from TCOF-DOX-PEGs. Finally, we demonstrated the utility of TCOF-PEG as an in vitro drug delivery system in HeLa cells. TCOF-DOX-PEG exhibited time-dependent release of DOX followed by internalization. Thus, the novel TCOF system reported here opens a new window in COF research for sensitive drug carrier systems.Physicochemical, electrochemical and biological performance of 4 types of all-carbon nanotube layers was studied. Higher oxidation state of carbon was responsible for micro-scaled uniformity of the layers and excellent electrical conductivity, while nitrogen containing functional groups yielded materials with anisotropy similar to natural tissues and reduced work function. All materials were cytocompatible with mammalian fibroblasts (viability >80%, cytotoxicity 80% reduction in the melanoma cells number, connected with enhanced production of reactive oxygen species (ROS) was observed. All-carbon nanotube layers decreased bacteria and cancer cell functions without negatively influencing mammalian cells nor using drugs and we believe that this can be explained by various sensitivity of the tested cells towards exogenous ROS overproduction. As the concerns over implant-related infections as well as rates of antibiotic-resistant bacteria and chemotherapeutic-resistant cancer cells are growing, such materials should pave the way for a wide range of biomedical applications.Pelvic organ prolapse (POP) is a multifactorial condition characterized by the descent of the pelvic organs due to the loss of supportive tissue strength. This is presumably caused by the decreased fibroblast function and the subsequent change in the quality of the extracellular matrix. The correction of POP using an implant intends to provide mechanical support to the pelvic organs and to stimulate a moderate host response. Synthetic polypropylene (PP) implants were commonly used for the correction of prolapse. Although they were successful in providing support, these implants have been associated with clinical complications in the long term due to substantial foreign body response and inappropriate tissue integration. The complications can be avoided or minimized by engineering a biocompatible and fully absorbable implant with optimized mechanical and structural characteristics that favor more appropriate cellular interactions with the implant. Therefore, in this study, we evaluated implants comprised of po1 ± 0.75) was significantly (P less then 0.005) smaller than those cultured on P4HB implants (average 2.31 ± 0.09). The P4HB structure with rounded pores showed the lowest stiffness and highest fibroblast attachment and proliferation (P less then 0.01). Overall, P4HB induces more matrix deposition compared to PP and knit design can further optimize cell behavior.Injury of articular cartilage leads to an imbalance in tissue homeostasis, and due to the poor self-healing capacity of cartilage the affected tissue often exhibits osteoarthritic changes. In recent years, injectable and highly tunable composite hydrogels for cartilage tissue engineering and drug delivery have been introduced as a desirable alternative to invasive treatments. In this study, we aimed to formulate injectable hydrogels for drug delivery and cartilage tissue engineering by combining different concentrations of hyaluronic acid-tyramine (HA-Tyr) with regenerated silk-fibroin (SF) solutions. Upon enzymatic crosslinking, the gelation and mechanical properties were characterized over time. To evaluate the effect of the hydrogel compositions and properties on extracellular matrix (ECM) deposition, bovine chondrocytes were embedded in enzymatically crosslinked HA-Tyr/SF composites (in further work abbreviated as HA/SF) or HA-Tyr hydrogels. We demonstrated that all hydrogel formulations were cytocompatible and could promote the expression of cartilage matrix proteins allowing chondrocytes to produce ECM, while the most prominent chondrogenic effects were observed in hydrogels with HA20/SF80 polymeric ratios. Unconfined mechanical testing showed that the compressive modulus for HA20/SF80 chondrocyte-laden constructs was increased almost 10-fold over 28 days of culture in chondrogenic medium which confirmed the superior production of ECM in this hydrogel compared to other hydrogels in this study. Furthermore, in hydrogels loaded with anabolic and anti-inflammatory drugs, HA20/SF80 hydrogel showed the longest and the most sustained release profile over time which is desirable for the long treatment duration typically necessary for osteoarthritic joints. click here In conclusion, HA20/SF80 hydrogel was successfully established as a suitable injectable biomaterial for cartilage tissue engineering and drug delivery applications.