Evaluation of cytotoxic potential of loratadine and the combination of loratadine and cisplatin on hepatocellular carcinoma cell lines

Hepatocellular carcinoma (HCC) has been a major health problem in Egypt with extensive efforts and studies done in enhancing chemotherapeutic drugs for more optimal results. Existing chemotherapeutic drugs are costly with problematic side effects. Recent studies have demonstrated the anticancer potential of antihistamines on different types of cancer, including HCC. Antihistamines have been proven to induce cell cycle arrest and/or apoptosis through different mechanisms depending on their role on different cancer types. The second generation antihistamine, loratadine (LOR), was found to have tumor inhibiting effects on human colon carcinoma cell line. However, no studies were done neither on the influence of loratadine on HCC cells, nor the effect of the combination of loratadine with existing chemotherapeutic drugs to test its potential to improve chemotherapy. Here, the cytotoxic potential of loratadine and the combination of loratadine and cisplatin on HepG2 and SNU449 were investigated. Cell viability assay was performed to show that there is a dose-dependent cytotoxic effect of LOR on both HCC cell lines and that there is a synergistic to additive effects when LOR was introduced to the cells in combination with cisplatin when the IC50 of both drugs were used. Loratadine did not show a cytotoxic effect on normal cells when used in low concentrations (\u3c55.6 µM). However, when used in higher concentration (\u3c73.2 µM), LOR showed a high cytotoxic effect. Apoptotic and cell cycle analysis showed that loratadine induced apoptosis and cell cycle arrest in the G2/M phase in SNU449 cells, while combination of loratadine and cisplatin may induce necrosis and cell cycle arrest in G2/M phase. Taken together, loratadine offers a strong basis to be further developed either alone or in combination with cisplatin as a treatment option for advanced hepatocellular carcinoma. Further studies are required to test the effect of loratadine treatment in vivo and perhaps to test the effect of loratadine in combination with sorafenib in vitro and in vivo for the hope to improve HCC therapy

A nullimorphic ERLIN2 mutation defines a complicated hereditary spastic paraplegia locus (SPG18)

Hereditary Spastic Paraplegia (HSP) is a clinically and genetically heterogeneous group of neurological disorders that are characterized by progressive spasticity of the lower extremities. We describe an extended consanguineous Saudi family in which HSP is linked to SPG18, a previously reported autosomal recessive locus, and show that it is associated with a nullimorphic deletion of ERLIN2, a component of endoplasmic reticulum associated degradation. This finding adds to the growing diversity of cellular functions that are now known to be involved in the maintenance of the corticospinal tract neurons

Inkjet-printed electrochemical devices for bioelectronics

In recent years, inkjet printing has received increasing attention from academic and industrial communities as a rapid prototyping and cost-effective tool for manufacturing a wide variety of electronic devices. The printed electronic field has great application in biosensors since printed sensors are cheap, small, portable and flexible. Therefore, substantial efforts have been devoted to the improvement of this powerful technology to render it suitable for microscale fabrication with the prospect of practical applications. The purpose of this research is to create a new alternative platform for developing diagnostic tools with high sensitivity and low cost. In this dissertation, I propose an alternative approach for sensitive detection of disease biomarkers and cardiac action potential using printed technology. This alternative approach is based on three main elements (i) controlled bioreceptor immobilization using photonic immobilization technique, (ii) signal amplification using electrochemical redox cycling, (iii) novel printing methodology. The first is achieved by combining a rapid and simple printing scheme with the photonic immobilization technique for site-specific immobilization of antibodies. Pho-tonic immobilization, which is easy and fast to perform, is presented on printed chips for the first time, achieving a higher sensitivity and better limit of detection compared to the conventional immobilization approaches. In the first application, I targeted the determination of C-reactive protein (CRP) in the presence of human serum. The second element, which is signal amplification using electrochemical redox cycling, is realized by repetitive cycling of redox probes between two adjacent electrodes. The sensitivity of a redox cycling sensor depends on the distance between the two electrodes. In other words, a short distance between the electrodes in the micro- or even nanometer regime is required to achieve an effective redox cycling amplification. Therefore, I developed a new scheme for fabricating micro-gap electrodes with in-plane displacement, as well as porous nano-gap electrodes with out-of-plane displacement, using inkjet printing and without prior surface patterning. As a proof of concept, I demonstrated the use of micro-gap redox cycling sensors for the detection of single-stranded DNA (ssDNA) using peptide nucleic acids (PNAs) immobilized on the carbon microelectrodes. The developed genosensors were then applied to the detection of human immunodeficiency virus-1 (HIV-1) marker sequence encoding of HIV-1 nef gene. The third element, namely the development of novel printing methodology for high-resolution printing, is accomplished by exploring the different physical, chemical and hydro-dynamical properties of an ink droplet that interacts with the substrate surface. I provide the first demonstration for fabricating microelectrode arrays (MEA) in a rapid prototyping approach based on inkjet printing. The printed MEAs on flexible substrates resulted in a high-resolution outcome with good electrical and outstanding electrochemical characteristics, suitable for cellular recording and stimulation. I cultured Hl-1 cells on MEAs printed using gold and carbon inks on flexible substrates. Using the MEAs, the propagating action potentials were recorded across the cellular network with high signal-to-noise ratios. The benefits of having a transparent and flexible printed MEA are well appreciated when it comes to in-vivo applications, such as neuronal implants. With such an application in mind, I printed high resolution MEAs on soft materials such as PDMS, agarose, and gelatin-based substrates including gummy bears. A series of in-vitro extracellular recordings of action potentials were recorded from cardiac HL-1 cells and the results demonstrate that inkjet printing can be used for fabricating functional cell-device interfaces on soft materials in a rapid prototyping approach. Hereafter, this dissertation contributes significantly to the vision I have for providing healthcare system with sensitive biosensors and soft MEA platforms that avoid expensive fabrication utilities, towards rapid prototyping of ultra-low-cost medical devices

Three-dimensional inkjet-printed redox cycling sensor

Multilayer inkjet printing is emerging as a robust platform for fabricating flexible electronic devices over a large area. Here, we report a straightforward, scalable and inexpensive method for printing multilayer three-dimensional nanoporous redox cycling devices with a tunable nanometer gap for electrochemical sensing. The fabrication of the electrochemical redox cycling device is based on vertical stacking of two conductive electrodes made of carbon and gold nanoparticle inks. In this configuration, the two electrodes are parallel to each other and electrically separated by a layer of polystyrene nanospheres. As the top and the bottom electrodes are biased to, respectively, oxidizing and reducing potentials, repetitive cycling of redox molecules between them generates a large current amplification. We show that a vertical interelectrode spacing down to several hundred nanometers with high precision using inkjet printing is possible. The printed sensors demonstrate excellent performance in electrochemical sensing of ferrocene dimethanol as a redox-active probe. A collection efficiency of 100% and current amplification up to 30-fold could be obtained. Our method provides a low cost and versatile means for sensitive electrochemical measurements eliminating the need for sophisticated fabrication methods, which could prove useful for sensitive point-of-care diagnostics devices

All-inkjet-printed gold microelectrode arrays for extracellular recording of action potentials

Inkjet printing is an attractive method for cost-effective additive manufacturing of electronic devices. Especially for applications where disposable sensor systems are of interest, it is a promising tool since it enables the production of low-cost and flexible devices. In this work, we report the fabrication of a disposable microelectrode array (MEA) using solely inkjet printing technology. The MEAs were fabricated with two different functional inks, a self-made gold ink to print conductive feedlines and electrodes and a polymer-based ink to add a dielectric layer for insulation of the feedlines. We printed different MEA designs of up to 64 electrodes with a minimum lateral spacing of 200 μm and a minimum electrode diameter of ~31 μm. As a proof-of-concept, extracellular recordings of action potentials from cardiomyocyte-like HL-1 cells were performed using the all-printed devices. Furthermore, we stimulated the cells during the recordings with noradrenaline, which led to an increase in the recorded beating frequency of the cells. The results demonstrate the feasibility of inkjet printing gold MEAs for cell-based bioelectronics