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One of the most significant hurdles to the affordable, accessible delivery of cell therapy is the cost and difficulty of expanding cells to clinically relevant numbers. Immunotherapy to prevent autoimmune disease, tolerate organ transplants or target cancer critically relies on the expansion of specialized T cell populations. We have designed 3D-printed cell culture lattices with highly organized micron-scale architectures, functionalized via plasma polymerization to bind monoclonal antibodies that trigger cell proliferation. This 3D technology platform facilitate the expansion of therapeutic human T cell subsets, including regulatory, effector, and cytotoxic T cells while maintaining the correct phenotype. Lentiviral gene delivery to T cells is enhanced in the presence of the lattices. Incorporation of the lattice format into existing cell culture vessels such as the G-Rex system is feasible. This cell expansion platform is user-friendly and expedites cell recovery and scale-up, making it ideal for translating T cell therapies from bench to bedside. [ABSTRACT FROM AUTHOR]

Abstract: In the field of stem cell technology, future advancements rely on the effective isolation, scale-up and maintenance of specific stem cell populations and robust procedures for their directed differentiation. The stem cell microenvironment – or niche – encompasses signal inputs from stem cells, supporting cells and from the extracellular matrix. In this context, the contribution of physicochemical surface variables is being increasingly recognised. This paradigm can be exploited to exert control over cellular behaviour. However, the number of parameters at play, and their complex interactions, presents a formidable challenge in delineating how the decisions of cell fate are orchestrated within the niche. Additionally, in the case of mesenchymal stem cells (MSC), more than one type of stem cell niche has been identified. By employing high throughput screening (HTS) strategies, common and specific attributes of each MSC niche can be probed. Here, we explore biological, chemical and physical parameters that are known to influence MSC self-renewal and differentiation. We then review techniques and strategies that allow the HTS of surface properties for conditions that direct stem cell fate, using MSC as a case study. Finally, challenges in recapturing the niche, particularly its three dimensional nature, in surface-based HTS formats are discussed. [Copyright &y& Elsevier]

Thecell microarray format can recreate a multitude of cell microenvironmentson a single chip using only minimal amounts of reagent. In this study,we describe surface modifications to passivate cell microarrays, aimingto adapt the platform to the study of stem cell behavior over long-termculture periods. Functionalization of glass slides with (3-glycidyloxypropyl)trimethoxysilane enabled covalent anchoring of extracellular matrixproteins on microscale spots printed by a robotic contact printer.Subsequently, the surface was passivated by bovine serum albumin (BSA)or poly(ethylene glycol)bisamine (A-PEG) with molecular weights of3000, 6000, and 10 000 Da. Cloud-point conditions for A-PEGgrafting were attained that were compatible with protein deposition.Passivation strategies were assessed by culturing mesenchymal stemcells on the microarray platform. While both BSA and A-PEG passivationinitially blocked cell adhesion between the printed spots, only A-PEGgrafting was able to maintain cell pattern integrity over the entireculture period of 3 weeks. [ABSTRACT FROM AUTHOR]

Abstract: Interfacing mammalian cells with single-walled carbon nanotubes (SWCNTs) has been considered a potential route for various bioengineering applications. Here, the interaction between human neuroblastoma cell line, SK-N-SH, with catalyst-free SWCNT-decorated porous silicon (pSi) substrates is investigated. SWCNT-decorated surfaces were fabricated by chemically attaching carboxy-functional SWCNTs to pSi functionalized via an amino silane. SWCNT attachment was confirmed by atomic force microscopy and Raman spectroscopy. Patterning of the amino silane on pSi by photolithography permitted the creation of patterned SWCNT-decorated pSi substrates. The number of cells attaching to the SWCNT decorated surface was observed to correlate with SWCNT density, implying that vertically aligned SWCNTs allowed the capture of cells. By incorporating a low fouling PEG silanization surface modification into the procedure, cell patterning was achieved on the fabricated SWCNT patterns. These SWCNT-decorated pSi substrates could potentially find application in lab-on-chip devices, particularly as platforms for the electrical stimulation of neuronal cells. [Copyright &y& Elsevier]

Abstract: We report on the synthesis of two carboxy-functional alkene compounds as modifiers of porous silicon (pSi) surface chemistry by means of thermal hydrosilylation. Both alkene compounds have hydrophobic, aliphatic carbon segments, with terminal carboxylic acid functionality appended through a thioether linkage. In one of the alkene linkers, we incorporated a short oligoethylene glycol (OEG) moiety to explore its low-fouling properties when attached to porous silicon. We examined surface stability of the surface-modified porous silicon in aqueous milieu. Albumin and fibronectin were adsorbed and, using carbodiimide chemistry, covalently immobilised to linker-modified porous silicon, and the propensity for mammalian cells to attach to these surfaces investigated. Surface chemistry was characterised by infrared spectroscopy and the stability of porous silicon in an aqueous milieu was investigated by interferometric reflectance spectroscopy (IRS). Surfaces functionalised with the alkene linker containing OEG displayed greater resistance to the adsorption of albumin. This linker also facilitated higher levels of covalent protein immobilisation to the functionalised pSi surface. Higher levels of cell attachment were observed on pSi surfaces with fibronectin covalently immobilised onto the OEG linker, than for fibronectin covalently immobilised on the non-OEG linker. [Copyright &y& Elsevier]

The article discusses various reports published within the issue, including one by Ali Hlongwane on the illustration of the prolonged divergence of opinion involved in remembering the historical trail of student activists in 1976 and another by Jordache Ellapen on the effect of cinematic choices in apartheid South African filmmaking.

Drawing on the media in several countries on the continent of Africa and in the UK, in this article I explore the different ways in which the media produces and presents visual images of Africa. The various images of Africa have of course been dependent on two main factors: firstly, the development of technology and subsequent access to it; and secondly, the ideology and ethos informing the use of the technology. I begin by considering an unlikely candidate for radical change, the Big Brother Africa programme broadcast on satellite television from South Africa and suggest that it is the very absence of an overt ideology that enables it to have the potential to break the mould of the customary crisis-ridden images from Africa on UK television. I then go on to consider two programmes broadcast on Channel Four in the UK which attempt to confront this 'crisis-ridden' image of Africa. I next consider images produced by African television programme makers, 'video-movie' directors or film makers based in African countries, and which are designed either for the home market or an international one. There are similarities and differences between the distinct technologies; each produces its own images of Africa which are very different. In each case, the state has sought to influence the ideology of the output, but only in the case of television has it been able to impose any substantial process of censoring. [ABSTRACT FROM AUTHOR]

Focuses on the practice of Theatre for Development in real life. Difficulties encountered of the program in assuming the role of the theatre; Discovery of the right to speak, the ability to articulate a point of view through performing; Revelation of another identity during the play.

Deals with the theater performance of Africans. Five stages of the transition from not-acting into acting to describe the range of human behavior that constitutes the presentation of the self in a special way; Details on the three modalities of theater.

States that performing in an African context can be divided into two categories. What are those categories and what do they represent; Identity of performers; What are the key elements; Understanding of African masked performance; Principle categories of characters; Describing audience reaction to masked warrior; Interaction between performers and the audience.

Features how the Tiv people of Nigeria use carved wooden masks and figures in their contemporary puppet and masquerade theater called kwagh-hir. Cultural meaning of masquerade in Africa; Performers of kwagh-hir; History of kwagh-hir; Material forms of kwagh-hir.

Protein biomarkers represent specific biological activities and processes, so they have had a critical role in cancer diagnosis and medical care for more than 50 years. With the recent improvement in proteomics technologies, thousands of protein biomarker candidates have been developed for diverse disease states. Studies have used different types of samples for proteomics diagnosis. Samples were pretreated with appropriate techniques to increase the selectivity and sensitivity of the downstream analysis and purified to remove the contaminants. The purified samples were analyzed by several principal proteomics techniques to identify the specific protein. In this study, recent improvements in protein biomarker discovery, verification, and validation are investigated. Furthermore, the advantages, and disadvantages of conventional techniques, are discussed. Studies have used mass spectroscopy (MS) as a critical technique in the identification and quantification of candidate biomarkers. Nevertheless, after protein biomarker discovery, verification and validation have been required to reduce the false-positive rate where there have been higher number of samples. Multiple reaction monitoring (MRM), parallel reaction monitoring (PRM), and selected reaction monitoring (SRM), in combination with stable isotope-labeled internal standards, have been examined as options for biomarker verification, and enzyme-linked immunosorbent assay (ELISA) for validation. [ABSTRACT FROM AUTHOR]

Underage drinking and its associated problems have profound negative consequences for underage drinkers themselves, their families, their communities, and society as a whole, and contribute to a wide range of costly health and social problems. There is increased risk of negative consequences with heavy episodic or binge drinking. Alcohol is a factor related to approximately 4,300 deaths among underage youths in the U.S. every year. Since the mid-1980s, the nation has launched aggressive underage drinking prevention efforts at the federal, state, and local levels, and national epidemiologic data suggest that these efforts are having positive effects. For example, since 1982, alcohol-related traffic deaths among youth aged 16-20 years have declined by 79%. Evidence-based or promising strategies for reducing underage drinking include those that limit the physical, social, and economic availability of alcohol to youth, make it illegal for drivers aged <21 years to drive after drinking, and provide mechanisms for early identification of problem drinkers. Strategies may be implemented through a comprehensive prevention approach including policies and their enforcement, public awareness and education, action by community coalitions, and early brief alcohol intervention and referral programs. This paper focuses on underage drinking laws and their enforcement because these constitute perhaps the most fundamental component of efforts to limit youth access to and use of alcohol. [ABSTRACT FROM AUTHOR]

This article discusses the issue of media programming in Africa. The dissemination of information and entertainment are two predominant dimensions of media. Radio and television are largely controlled by governments, while film and video-movies have a much greater degree of independence, both in funding and production. In this issue, the author has brought together writers, whose articles on the forms of media inform readers about some of the most innovative media practices in which people take some control of their own lives and where media practitioners respect the non-professional.

A label-free porous silicon (pSi) based, optical biosensor, using both an antibody and aptamer bioreceptor motif has been developed for the detection of insulin. Two parallel biosensors were designed and optimised independently, based on each bioreceptor. Both bioreceptors were covalently attached to a thermally hydrosilylated pSi surface though amide coupling, with unreacted surface area rendered stable and low fouling by incorporation of PEG moieties. The insulin detection ability of each biosensor was determined using interferometric reflectance spectroscopy, using a range of different media both with and without serum. Sensing performance was compared in terms of response value, response time and limit of detection (LOD) for each platform. In order to demonstrate the capability of the best performing biosensor to detect insulin from real samples, an in vitro investigation with the aptamer-modified surface was performed. This biosensor was exposed to buffer conditioned by glucose-stimulated human islets, with the result showing a positive response and a high degree of selectivity towards insulin capture. The obtained results correlated well with the ELISA used in the clinic for assaying glucose-stimulated insulin release from donor islets. We anticipate that this type of sensor can be applied as a rapid point-of-use biosensor to assess the quality of donor islets in terms of their insulin production efficiency, prior to transplantation. [ABSTRACT FROM AUTHOR]

Porous silicon (pSi) substrates are a promising platform for cell expansion, since pore size and chemistry can be tuned to control cell behavior. In addition, a variety of bioactives can be loaded into the pores and subsequently released to act on cells adherent to the substrate. Here, we construct a cell microarray on a plasma polymer coated pSi substrate that enables the simultaneous culture of human endothelial cells on printed immobilized protein factors, while a second soluble growth factor is released from the same substrate. This allows three elements of candidate pSi scaffold materialstopography, surface functionalization, and controlled factor releaseto be assessed simultaneously in high throughput. We show that protein conjugation within printed microarray spots is more uniform on the pSi substrate than on flat glass or silicon surfaces. Active growth factors are released from the pSi surface over a period of several days. Using an endothelial progenitor cell line, we investigate changes in cell behavior in response to the microenvironment. This platform facilitates the design of advanced functional biomaterials, including scaffolds, and carriers for regenerative medicine and cell therapy. [ABSTRACT FROM AUTHOR]

Porous silicon (pSi) materials are regarded as promising drug delivery vehicles due to their biocompatibility, in vivo degradation, and resorption. We examine pSi films as a platform for the controlled delivery of levothyroxine, as a means to overcome problems with consistent dosage of this drug by oral administration. Oxidized pSi films were modified with 3-(aminopropyl)triethoxysilane (APTES), creating a surface chemistry that increased levothyroxine drug loading capacity by 50% and sustained drug release under physiological conditions for 14 days. Release kinetics from APTESfunctionalized films initially followed a zero-order release profile, which is highly desirable for drug delivery. The loading and release profiles of levothyroxine suggest that the film size required to deliver a therapeutic dose is feasible for further consideration as an implantable delivery system. [ABSTRACT FROM AUTHOR]

The evolving US opioid crisis is complex and requires myriad different interventions. These include reducing opioid overprescribing and curtailing the supply of illicit opioids, overdose rescue interventions, and treatment and recovery support services for those with opioid use disorders. To date, more distal primary prevention strategies that have an evidence base are underutilized. Yet, the impact of early environments on later substance use disorder risk is increasingly well understood, including knowledge of the mechanistic linkages between brain development and subsequent risk behaviors. Applying this developmental framework to prevention shows promise, and some middle-school interventions have demonstrated significant reductions in prescription opioid misuse. Reducing these risks of initial misuse of opioids may be the "ounce of prevention" that makes a substantial difference in a society now reeling from the worst drug crisis our country has seen. The challenge is to continue to develop and test promising distal interventions and to support implementation fidelity through frameworks that ensure their cultural appropriateness and sustainability. In addition, research is needed to develop new prevention strategies for adults, including patients with pain at risk for transitioning from prescription to illicit opioids. [ABSTRACT FROM AUTHOR]

Abstract: Microfluidic 3D cell culture is a promising technology for the screening of drug toxicity profiles. In this study, a bioartificial liver consisting of a surface‐engineered microfluidic silicon chip with microtrenches mimicking hepatic sinusoids is shown to extend 3D primary hepatocyte culture and improve in vitro drug screening for hepatotoxicity, with respect to the state‐of‐the‐art literature on this subject. Primary hepatocytes hosted in the 3D heparin‐coated microtrenches (the bioartificial liver) secrete high levels of albumin and urea over 4 weeks. The cytotoxicity of common drugs, namely, acetaminophen, chlorpromazine, and tacrine, was assessed on primary hepatocytes both at day 1 and day 7. The results suggest that mimicking hepatic sinusoids using a microtrench format allows the maintenance of difficult‐to‐culture primary hepatocytes to be extended to 4 weeks and provides an alternative model to animal studies for the screening of the cytotoxicity of new drugs. [ABSTRACT FROM AUTHOR]

The propensity of glycosaminoglycans to mediate cell–cell and cell–matrix interactions opens the door to capture cells, including circulating blood cells, onto biomaterial substrates. Chondroitin sulfate (CS)-B is of particular interest, since it interacts with the receptor (EGF)-like module-containing mucin-like hormone receptor-like 2 precursor (EMR2) displayed on the surface of leukocytes and endothelial progenitor cells. Herein, CS-B and its isomer CS-A were covalently immobilized onto heptylamine plasma polymer films via three different binding chemistries to develop platform technology for the capture of EMR2 expressing cells onto solid carriers. Surface characterization verified the successful immobilization of both glycosaminoglycans. The EMR2 expressing human myeloid cell line U937 preferentially bound onto CS-B-modified substrates, and U937 cells preincubated with CS-B in solution exhibited reduced affinity for the substrate. The direct capture of hematopoietic and blood-circulating endothelial cell types via a glycosaminoglycan-binding surface receptor opens an unexplored route for the development of biomaterials targeted at these cell types. [ABSTRACT FROM AUTHOR]

Pancreatic islet transplantation has become a recognized therapy for insulin-dependent diabetes mellitus. During isolation from pancreatic tissue, the islet microenvironment is disrupted. The extracellular matrix (ECM) within this space not only provides structural support, but also actively signals to regulate islet survival and function. In addition, the ECM is responsible for growth factor presentation and sequestration. By designing biomaterials that recapture elements of the native islet environment, losses in islet function and number can potentially be reduced. Cell microarrays are a high throughput screening tool able to recreate a multitude of cellular niches on a single chip. Here, we present a screening methodology for identifying components that might promote islet survival. Automated fluorescence microscopy is used to rapidly identify islet derived cell interaction with ECM proteins and immobilized growth factors printed on arrays. MIN6 mouse insulinoma cells, mouse islets and, finally, human islets are progressively screened. We demonstrate the capability of the platform to identify ECM and growth factor protein candidates that support islet viability and function and reveal synergies in cell response. [ABSTRACT FROM AUTHOR]

Vertically aligned silicon nanowire (VA-SiNW) arrays are emerging as a powerful new tool for gene delivery by means of mechanical transfection. In order to utilize this tool efficiently, uncertainties around the required design parameters need to be removed. Here, a combination of nanosphere lithography and templated metal-assisted wet chemical etching is used to fabricate VA-SiNW arrays with a range of diameters, heights, and densities. This fabrication strategy allows identifi cation of critical parameters of surface topography and consequently the design of SiNW arrays that deliver plasmid with high transfection efficiency into a diverse range of human cells whilst maintaining high cell viability. These results illuminate the cell-materials interactions that mediate VA-SiNW transfection and have the potential to transform gene therapy and underpin future treatment modalities. [ABSTRACT FROM AUTHOR]

The critical growth factor density required to support neural lineage generation from mouse embryonic stem cells is assessed by constructing a surface density gradient of immobilized nerve growth factor (NGF) from a plasma polymer film base. A chemical surface gradient varying from high hydroxyl group density to high aldehyde group density is prepared through diffusion-controlled plasma polymerization of two monomers (ethanol and propionaldehyde) under a moving mask. NGF density gradients are then produced by reductive amination with the aldehyde groups on the plasma polymer surface. Mouse embryoid body derived (mEB) cell differentiation on the gradient surface is evaluated by immunofluorescence staining against Nestin. mEB cell density and the percentage of Nestin-positive cells increase with increasing NGF density up to a critical value corresponding to 52.9 ng cm−2, above which cell attachment and differentiation do not increase further. This gradient-based screening approach allows the growth factor surface densities to be optimized for biomaterials intended for cell differentiation or expansion, which is highly relevant to creating efficient manufacture processes for cell therapies. [ABSTRACT FROM AUTHOR]