Implementation and Effects of an Information Technology-Based Intervention to Support Speech and Language Therapy Among Stroke Patients With Aphasia: Protocol for a Virtual Randomized Controlled Trial.

BACKGROUND: Mobile app-based therapies are increasingly being employed by speech-language pathologists in the rehabilitation of people with aphasia as adjuncts or substitutes for traditional in-person therapy approaches. These apps can increase the intensity of treatment and have resulted in meaningful outcomes across several domains. OBJECTIVE: VoiceAdapt is a mobile therapy app designed with user and stakeholder feedback within a user-centered design framework. VoiceAdapt uses two evidence-based lexical retrieval treatments to help people with aphasia in improving their naming abilities through interactions with the app. The purpose of the randomized controlled trial (RCT) proposed here is to examine the feasibility and clinical efficacy of training with VoiceAdapt on the language and communication outcomes of people with aphasia. METHODS: A multicenter RCT is being conducted at two locations within Canada. A total of 80 people with aphasia will be recruited to participate in a two-arm, waitlist-controlled, crossover group RCT. After baseline assessment, participants will be randomized into an intervention group or a waitlist control group. The intervention group participants will engage in 5 weeks of training with the app, followed by posttreatment and follow-up assessments after an additional 5 weeks. Those in the waitlist control group will have no training for 5 weeks; this is followed by pretreatment assessment, training for 5 weeks, and posttreatment assessment. All trial procedures are being conducted remotely given the COVID-19 pandemic. RESULTS: Recruitment of participants started in September 2020, and the study is expected to be completed by March 2022. Publication of results is expected within 6 months of study completion. CONCLUSIONS: The results of the RCT will provide information on evidence-based practice using technology-based solutions to treat aphasia. If positive results are obtained from this RCT, the VoiceAdapt app can be recommended as an efficacious means of improving lexical retrieval and communicative functioning in people with aphasia in an easily accessible and a cost-effective manner. Moreover, the implementation of this RCT through remote assessment and delivery can provide information to therapists on telerehabilitation practices and monitoring of app-based home therapy programs. TRIAL REGISTRATION: ClinicalTrials.gov NCT04108364; https://clinicaltrials.gov/ct2/show/NCT04108364. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/30621.

Immobilization of Enzymes on PLGA Sub-Micrometer Particles by Crosslinked Layer-by-Layer Deposition.

Enzyme immobilization is of high interest for industrial applications. However, immobilization may compromise enzyme activity or stability due to the harsh conditions which have to be applied. The authors therefore present a new and improved crosslinked layer-by-layer (cLbL) approach. Two different model enzymes (acid phosphatase and ß-galactosidase) are immobilized under mild conditions on biocompatible, monodisperse, sub-micrometer poly(lactide-co-glycolide) (PLGA) particles. The resulting PLGA enzyme systems are characterized regarding their size, surface charge, enzyme activity, storage stability, reusability, and stability under various conditions such as changing pH and temperature. The developed and characterized cLbL protocol can be easily adapted to different enzymes. Potential future uses of the technology for biomedical applications are discussed. PLGA-enzyme particles are therefore injected into the blood circulation of zebrafish embryos in order to demonstrate the in vivo stability and activity of the designed system.

Protein phosphatase type 2Calpha and 2Cbeta are involved in fatty acid-induced apoptosis of neuronal and endothelial cells.

Unsaturated fatty acids with special structural features have been shown to activate serine/threonine protein phosphatase type 2C (PP2C) isoforms alpha and beta at physiological Mg(2+)-concentrations in vitro. These compounds also induce apoptosis in neuronal and endothelial cells. In this study we further analysed this striking correlation and tried to elucidate whether or not there is a causative relationship between activation of PP2C and induction of apoptosis. We employed RNA interference to simultaneously knock down PP2Calpha and PP2Cbeta in SH-SY5Y cells or HUVECs, respectively. This downregulation was transient. Treatment of SH-SY5Y cells or HUVECs with oleic acid (18:1,cis-Delta(9)) caused apoptosis in a time- and concentration-dependent manner. In both cases, cells with reduced PP2C-levels were less susceptible to oleic acid-induced cell damage. In conclusion, our results demonstrate that PP2C activation by unsaturated fatty acids actually causes apoptosis in neuronal and endothelial cells.

Oleic acid causes apoptosis and dephosphorylates Bad.

There is increasing evidence showing the involvement of unsaturated free fatty acids in cell death pathways, particularly in the context of apoptotic signalling. Our previous in vitro study has demonstrated that oleic acid, a monounsaturated fatty acid, reduces phosphorylation of proapoptotic Bad through activation of protein phosphatase type 2Cbeta. In the present study, we attempted to investigate the role of oleic acid in neuronal apoptosis using different types of cell cultures, and, furthermore, to explore the underlying mechanism with regard to its effect on Bad expression. As revealed by nuclear staining, oleic acid caused a concentration- and time-dependent damage with typical apoptotic features in cortical and hippocampal cultures from embryonic and neonatal rats, respectively, as well as in human neuroblastoma SH-SY5Y cells. In mixed hippocampal cultures, nearly all neurons were damaged at 24 h after the treatment, while damage of astrocytes was detected 48 h after adding this fatty acid, suggesting that neurons were more vulnerable than astrocytes. Nile blue staining showed that oleic acid and oleic acid methyl ester were both taken up by the neurons within 30 min. In contrast to oleic acid, oleic acid methyl ester did not change cell viability demonstrating that oleic acid-induced cell death was not due to an overload of the cells with lipids. Caspase-3 activity was not increased by oleic acid in cultured hippocampal cells. Western blot analysis of phospho-Ser112 Bad and the total Bad in cultured hippocampal cells revealed a significant decrease in the ratio of phospho-Ser112 Bad to total Bad in a time- and concentration-dependent manner after the exposure with oleic acid. We conclude that oleic acid induces neuronal apoptosis through a caspase-3-independent mechanism involving dephosphorylation of Bad.

Reciprocal inhibition of p53 and nuclear factor-kappaB transcriptional activities determines cell survival or death in neurons.

The tumor suppressor and transcription factor p53 is a key modulator of cellular stress responses, and activation of p53 precedes apoptosis in many cell types. Controversial reports exist on the role of the transcription factor nuclear factor-kappaB (NF-kappaB) in p53-mediated apoptosis, depending on the cell type and experimental conditions. Therefore, we sought to elucidate the role of NF-kappaB in p53-mediated neuron death. In cultured neurons DNA damaging compounds induced activation of p53, whereas NF-kappaB activity declined significantly. The p53 inhibitor pifithrin-alpha (PFT) preserved NF-kappaB activity and protected neurons against apoptosis. Immunoprecipitation experiments revealed enhanced p53 binding to the transcriptional cofactor p300 after induction of DNA damage, whereas binding of p300 to NF-kappaB was reduced. In contrast, PFT blocked the interaction of p53 with the cofactor, whereas NF-kappaB binding to p300 was enhanced. Most interestingly, similar results were observed after oxygen glucose deprivation in cultured neurons and in ischemic brain tissue. Ischemia-induced repression of NF-kappaB activity was prevented and brain damage was reduced by the p53 inhibitor PFT in a dose-dependent manner. It is concluded that a balanced competitive interaction of p53 and NF-kappaB with the transcriptional cofactor p300 exists in neurons. Exposure of neurons to lethal stress activates p53 and disrupts NF-kappaB binding to p300, thereby blocking NF-kappaB-mediated survival signaling. Inhibitors of p53 provide pronounced neuroprotective effects because they block p53-mediated induction of cell death and concomitantly enhance NF-kappaB-induced survival signaling.