A novel multi-stage enrichment workflow and comprehensive characterization for HEK293F-derived extracellular vesicles.

Extracellular vesicles (EVs) are emerging as a promising drug delivery vehicle as they are biocompatible and capable of targeted delivery. However, clinical translation of EVs remains challenging due to the lack of standardized and scalable manufacturing protocols to consistently isolate small EVs (sEVs) with both high yield and high purity. The heterogenous nature of sEVs leading to unknown composition of biocargos causes further pushback due to safety concerns. In order to address these issues, we developed a robust quality-controlled multi-stage process to produce and isolate sEVs from human embryonic kidney HEK293F cells. We then compared different 2-step and 3-step workflows for eliminating protein impurities and cell-free nucleic acids to meet acceptable limits of regulatory authorities. Our results showed that sEV production was maximized when HEK293F cells were grown at high-density stationary phase in semi-continuous culture. The novel 3-step workflow combining tangential flow filtration, sucrose-cushion ultracentrifugation and bind-elute size-exclusion chromatography outperformed other methods in sEV purity while still preserved high yield and particle integrity. The purified HEK293F-derived sEVs were thoroughly characterized for identity including sub-population analysis, content profiling including proteomics and miRNA sequencing, and demonstrated excellent preclinical safety profile in both in-vitro and in-vivo testing. Our rigorous enrichment workflow and comprehensive characterization will help advance the development of EVs, particularly HEK293F-derived sEVs, to be safe and reliable drug carriers for therapeutic applications.

Skin rejuvenation and photoaging protection using adipose-derived stem cell extracellular vesicles loaded with exogenous cargos.

BACKGROUND: Small extracellular vesicles from adipose-derived stem cells (ASC-sEVs) have gained remarkable attention for their regenerative and protective properties against skin aging. However, the use of ASC-sEVs to further encapsulate certain natural anti-aging compounds for synergistic effects has not been actively explored. For large-scale production in skincare industry, it is also crucial to standardize cost-effective methods to produce highly pure ASC-sEVs. METHODS: Human ASCs were expanded in serum-free media with different compositions to first optimize the sEV production. ASC-sEVs from different batches were then purified using tangential flow filtration and sucrose cushion ultracentrifugation, followed by extensive characterization for identity and content profiling including proteomics, lipidomics and miRNA sequencing. ASC-sEVs were further loaded with nicotinamide riboside (NR) and resveratrol by sonication-incubation method. The therapeutic effect of ASC-sEVs and loaded ASC-sEVs was tested on human keratinocyte cell line HaCaT exposed to UVB by measuring reactive oxygen species (ROS). The loaded ASC-sEVs were later applied on the hand skin of three volunteers once a day for 8 weeks and skin analysis was performed every 2 weeks. RESULTS: Our standardized workflow produced ASC-sEVs with high yield, high purity and with stable characteristics and consistent biocargo among different batches. The most abundant subpopulations in ASC-sEVs were CD63+ (∼30%) and CD81+ -CD63+ (∼35%). Purified ASC-sEVs could be loaded with NR and resveratrol at the optimized loading efficiency of ∼20%. In UVB-exposed HaCaT cells, loaded ASC-sEVs could reduce ROS by 38.3%, higher than the sEVs (13.3%) or compounds (18.5%) individually. In human trial, application of loaded ASC-sEVs after 8 weeks substantially improved skin texture, increased skin hydration and elasticity by 104% and reduced mean pore volume by 51%. CONCLUSIONS: This study demonstrated a robust protocol to produce ASC-sEVs and exogenously load them with natural compounds. The loaded ASC-sEVs exhibited synergistic effects of both sEVs and anti-aging compounds in photoaging protection and skin rejuvenation.

Selection of Non-vitamin K Antagonist Oral Anticoagulant for Stroke Prevention in Atrial Fibrillation Based on Patient Profile: Perspectives from Vietnamese Experts. Part 2.

Part 1 of this review provided an overview of AF in Vietnam, with a particular focus on primary and secondary stroke prevention. Part 2 explores the management of AF in special, high-risk and clinically common patient populations, including those with renal impairment, diabetes, the elderly, and those with coronary artery disease. Furthermore, Part 2 addresses the challenges posed by patients with AF who have a bioprosthetic valve, a group situated in a grey area of consideration. Managing AF in these patient groups presents unique clinical challenges that require careful consideration. Physicians are tasked with addressing specific clinical questions to identify the optimal anticoagulation strategy for each individual. To inform these decisions, subgroup analyses from pivotal studies are presented alongside real-world data derived from clinical practice. By synthesising available information and considering the nuanced clinical context, the aim is to provide informed perspectives that align with current medical knowledge and contribute to the enhancement of patient care in these challenging scenarios.

Selection of Non-vitamin K Antagonist Oral Anticoagulant for Stroke Prevention in Atrial Fibrillation Based on Patient Profile: Perspectives from Vietnamese Experts. Part 1.

In Asia, especially Vietnam, AF is a common arrhythmia and is linked to a higher risk of stroke and systemic embolism. Anticoagulation therapy for stroke prevention in AF patients can result in bleeding complications. To effectively manage AF, adopting appropriate anticoagulation and addressing modifiable risk factors are crucial. Vietnamese clinicians are particularly interested in non-vitamin K antagonist oral anticoagulants (NOACs), a recent development in AF treatment. However, the lack of head-to-head trials comparing NOACs makes selecting a specific NOAC challenging. This review aims to provide a comprehensive overview of the available clinical evidence on NOACs for stroke prevention in AF to assist clinicians in making informed decisions and improving treatment outcomes in patients with AF. The first part of this review will present the current landscape of AF in Vietnam, focusing on AF prevalence and highlighting gaps in clinical practice. Furthermore, this part extensively discusses the anticoagulation strategy for both primary and secondary stroke prevention in AF.

A Review of the Effectiveness, Feasibility, and Acceptability of Art Therapy for Children and Adolescents during the COVID-19 Pandemic.

Art therapy has been widely offered to reduce symptoms of psychological disturbance. Pooled evidence about its effectiveness in epidemic contexts, particularly during the COVID-19 pandemic, has not been yet established. This study reviewed the effectiveness, feasibility, and acceptability of art therapy on children and adolescents during the COVID-19 pandemic and past epidemics. We searched PubMed/Medline, PsycINFO, CENTRAL (Cochrane Library), and CINAHL for articles on art therapy during COVID-19. Included studies reported improvements in measures of mental health, sleep quality, and psychological well-being in children with or without disabilities in the epidemic context. Results also showed that art therapy was highly feasible and accepted by children and adolescents as well as their families during epidemics in reviewed studies. Art therapy can be effective at improving various aspects of mental health, sleep quality, and psychological well-being. More empirical evidence is needed with larger sample sizes and longer duration of interventions.

Contralateral Inferior Alveolar Nerve Transposition for Simultaneous Dental Implant Placement on a Unilateral Reconstructed Mandible: A Case Report With a 7-Year Follow-Up.

This case report describes an unusual case of implant treatment after contralateral inferior alveolar nerve transposition (IANT) on a unilateral reconstructed mandible due to gunshot trauma with a 7-year follow-up. The patient had an edentulous atrophic mandible and underwent large bone reconstruction on the left side. The irregular passage of the right inferior alveolar nerve was within 1-2 mm of the superior aspect of the mandible, passed through the midline, and was nearly exposed under the oral mucosa at the left anterior part of the mandible, which prevented the placement of conventional implants. Consequently, right IANT followed by iliac onlay bone grafting was undertaken under general anesthesia to create a sufficient bone volume for implant placement. Four implants were installed simultaneously on the augmented bone. After a 2-month waiting period, soft tissue graft placement and vestibuloplasty were performed. The patient was scheduled for a continuous follow-up for the next 7 years. After 3 years, the bar-retained supporting system was replaced with the new CAD/CAM milled bar system on the same 4 implants. The 4 implants presented good initial stability (>35 N/cm), and radiographic evaluation showed osseointegration around all 4 implants. The patient experienced lip numbness in the first 5 days postoperatively but recovered by 97% after 2 months. After a 7-year follow-up, the result remained satisfactory with no sign of bone loss around any of the 4 implants, and the prosthesis functioned well and was stable and esthetically satisfactory. In conclusion, an immediate implant placement procedure after a complex surgery involving unilateral IANT and iliac onlay bone grafting remains challenging, especially when the patient has extensive bone defects or an atrophic mandible. However, a successful long-term outcome can be achieved with appropriate perioperative and postoperative care.