Treatment of Human Immunodeficiency Virus-Associated Facial Lipoatrophy With Hyaluronic Acid Filler Mixed With Micronized Cross-Linked Acellular Dermal Matrix

Decellularized Extracellular Matrix Scaffolds for Soft Tissue Augmentation: From Host-Scaffold Interactions to Bottlenecks in Clinical Translation

Along with a paradigm shift in looking at soft tissue fillers from space-filling to bioactive materials, decellularized extracellular matrix (DEM) fillers have gained more attention considering their superior bioactivity. However, the complex mechanisms that govern the interaction between host tissues and DEMs have been partially understood. This review first covers the mechanisms that determine immunogenicity, angiogenesis and vasculogenesis, and recellularization and remodeling after DEM implantation into host tissue, with a particular focus on related findings from filler materials. Accordingly, the review delves into the dual role of macrophages and their M1/M2 polarization paradigm to form both constructive and destructive immune responses to DEM implants. Moreover, the contribution of macrophages in angiogenesis has been elucidated, which includes but is not limited to the secretion of angiogenic growth factors and extracellular matrix (ECM) remodeling. The findings challenge the traditional view of immune cells as solely destructive entities in biomaterials and indicate their multifaceted roles in tissue regeneration. Furthermore, the review discusses how the compositional factors of DEMs, such as the presence of growth factors and matrikines, can influence angiogenesis, cell fate, and differentiation during the recellularization process. It is also shown that the biomechanical properties of DEMs, including tissue stiffness, modulate cell responses through mechanotransduction pathways, and the structural properties of DEMs, such as scaffold porosity, impact cell-cell and cell-ECM interactions. Finally, we pointed out the current clinical applications, the bottlenecks in the clinical translation of DEM biomaterials into soft tissue fillers, as well as the naïve research areas of the field.

Acellular dermal matrix in urethral reconstruction

The management of severe urethral stricture has always posed a formidable challenge. Traditional approaches such as skin flaps, mucosal grafts, and urethroplasty may not be suitable for lengthy and intricate strictures. In the past two decades, tissue engineering solutions utilizing acellular dermal matrix have emerged as potential alternatives. Acellular dermal matrix (ADM) is a non-immunogenic biological collagen scaffold that has demonstrated its ability to induce layer-by-layer tissue regeneration. The application of ADM in urethral reconstruction through tissue engineering has become a practical endeavor. This article provides an overview of the preparation, characteristics, advantages, and disadvantages of ADM along with its utilization in urethral reconstruction via tissue engineering.

COVID-19 mRNA vaccines as hypothetical epigenetic players: Results from an in silico analysis, considerations and perspectives

OBJECTIVES

To investigate in silico the occurrence of epigenetic crosstalk by nucleotide sequence complementarity between the BNT162b2 mRNA vaccine and whole human genome, including coding and noncoding (nc)RNA genes. To correlate these results with those obtained with the original spike (S) gene of Severe Acute Respiratory Syndrome CoronaVirus-2 (SARS-CoV-2).

METHODS

The publicly available FASTA sequence of the BNT162b2 mRNA vaccine and the SARS-CoV-2 isolate Wuhan-Hu-1 S gene (NC_045512.2) were used separately as key input to the Ensembl.org library to evaluate base pair match to human GRCh38 genome. Human coding and noncoding genes harboring hits were assessed for functional activity and health effects using bioinformatics tools and GWAS databases.

RESULTS

The BLAT analysis against the human GRCh38 genome revealed a total of 37 hits for BNT162b2 mRNA and no hits for the SARS-CoV-2 S gene. More specifically, BNT162b2 mRNA matched 19 human genes whose protein products are variously involved in enzyme reactions, nucleotide or cation binding, signaling, and carrier functions. In BLASTN analysis of ncRNA genes, BNT162b2 mRNA and SARS-CoV-2 S gene matched 17 and 24 different human genomic regions, respectively. Overall, characterization of the matched noncoding sequences revealed stronger interference with epigenetic pathways for BNT162b2 mRNA compared with the original S gene.

CONCLUSION

This pivotal in silico analysis shows that SARS-CoV-2 S gene and the BNT162b2 mRNA vaccine exhibit Watson-Crick nucleotide complementarity with human coding or noncoding genes. Although they do not share the same complementarity pattern, both may disrupt epigenetic mechanisms in target cells, potentially leading to long-term complications.

COVID-19 and metabolic syndrome

Convergence of the two pandemics: metabolic syndrome and COVID-19 over last two years has posed unprecedented challenges to individuals as well as healthcare systems. Epidemiological data suggest a close association between metabolic syndrome and COVID-19 while variety of possible pathogenic connections have been proposed while some have been proven. Despite the evidence of high risk for adverse COVID-19 outcomes in people with metabolic syndrome, little is known about the differences in efficacy and safety among people with metabolic syndrome and without. It is important to recognize that among people with metabolic syndrome This review summarizes the current knowledge and epidemiological evidence on the association between metabolic syndrome and adverse COVID-19 outcomes, pathogenic interrelationships, management considerations for acute COVID-19 and post-COVID sequalae and sustaining care of people living with metabolic syndrome with appraisal of evidence and gaps in knowledge.

COVID-19 vaccine had a significant positive impact on patients with SARS-COV-2 during the third (Omicron) wave in Saudi Arabia

INTRODUCTION

The third (Omicron) wave had caused significant increase in the number of COVID-19 cases around the globe. The severity of the disease dependeds on the extent of the vaccination status.

METHODS

This is a retrospective study of infected COVID-19 patients during the third (Omicron) wave in a hospital in Saudi Arabia.

RESULTS

A total of 400 patients were included with 220 (55 %) males and 180 (45 %) females, and a mean age (+/- SD) of 36.34 + 16.47 years. The most common presenting symptoms were: sore throat 159 (39.8 %), cough 158 (39.5 %), fever 132 (33 %), headache 122 (30.5 %), and muscle ache 124 (31%). There was no difference in underlying conditions, signs and symptoms between males and females apart from the occurrence of sore throat with an OR of 2.014 (95 % CI: 1.103-3.677, P = 0.023) and need of hospitalization OR 2.457 (95 % CI: 1.168-5.167, P value =.018) in a binary logistic regression comparison. The need for hospitalization was inversely related to the number of COVID-19 vaccination doses. The rate of admission was 8 (72.7 %), 34 (12 %), 4 (5.4 %) for one, two, and three doses of COVID-19 vaccine, respectively (P < 0.0001). Of all the patients, 14 (3.5 %) and 8 (2 %) required intensive care (ICU) admission and mechanical ventilation, respectively. The median Ct-value of SARS-CoV-2 was higher in those who had 2 or 3 doses compared to those who had one dose of the COVID-19 vaccine, but the difference did not reach statistical significance. None of the included patients died during the study period.

CONCLUSION

Omicron variant symptoms among infected patients are generally milder compared to other variants. Prior COVID-19 vaccination may limit disease severity and need for hospitalization.

Frozen bean curd-inspired Xenogeneic acellular dermal matrix with triple pretreatment approach of freeze-thaw, laser drilling and ADSCs pre-culture for promoting early vascularization and integration

Xenogeneic acellular dermal matrix (ADM) is widely used in clinical practice given its good biocompatibility and biomechanical properties. Yet, its dense structure remains a hindrance. Incorporation of laser drilling and pre-culture with Adipose-derived stem cells (ADSCs) have been attempted to promote early vascularization and integration, but the results were not ideal. Inspired by the manufacturing procedure of frozen bean curd, we proposed a freeze-thaw treatment to enhance the porosity of ADM. We found that the ADM treated with -80°C3R+-30°C3R had the largest disorder of stratified plane arrangement (deviation angle 28.6%) and the largest porosity (96%), making it an optimal approach. Human umbilical vein endothelial cells on freeze-thaw treated ADM demonstrated increased expression in Tie-2 and CD105 genes, proliferation, and tube formation in vitro compared with those on ADM. Combining freeze-thaw with laser drilling and pre-culture with ADSCs, such tri-treatment improved the gene expression of pro-angiogenic factors including IGF-1, EGF, and VEGF, promoted tube formation, increased cell infiltration, and accelerated vascularization soon after implantation. Overall, freeze-thaw is an effective method for optimizing the internal structure of ADM, and tri-treatments may yield clinical significance by promoting early cell infiltration, vascularization, and integration with surrounding tissues.

Novel Nanotechnology-Based Approaches for Targeting HIV Reservoirs

Highly active anti-retroviral therapy (HAART) is prescribed for HIV infection and, to a certain extent, limits the infection's spread. However, it cannot completely eradicate the latent virus in remote and cellular reservoir areas, and due to the complex nature of the infection, the total eradication of HIV is difficult to achieve. Furthermore, monotherapy and multiple therapies are not of much help. Hence, there is a dire need for novel drug delivery strategies that may improve efficacy, decrease side effects, reduce dosing frequency, and improve patient adherence to therapy. Such a novel strategy could help to target the reservoir sites and eradicate HIV from different biological sanctuaries. In the current review, we have described HIV pathogenesis, the mechanism of HIV replication, and different biological reservoir sites to better understand the underlying mechanisms of HIV spread. Further, the review deliberates on the challenges faced by the current conventional drug delivery systems and introduces some novel drug delivery strategies that have been explored to overcome conventional drug delivery limitations. In addition, the review also summarizes several nanotechnology-based approaches that are being explored to resolve the challenges of HIV treatment by the virtue of delivering a variety of anti-HIV agents, either as combination therapies or by actively targeting HIV reservoir sites.

Autologous Scar-Related Tissue Combined with Skin Grafting for Reconstructing Large Area Burn Scar

BACKGROUND

This study introduced a novel method to reconstruct large areas of scarring caused by burns via combining autologous scar-related tissue with spit-thickness skin grafting (ASTCS).

METHODS

25 patients underwent reconstruction after scar resection surgeries around the joints were analyzed between Jan 2012 and Jan 2018. Patient demographics and clinical parameters were collected, autologous scar-related tissue was modified to meshed structure, and the split-thickness skin was acquired from the scalp. The scar was resected and punched by a meshing machine with a thickness of 0.3-0.5 mm at a ratio of 1:1. The secondary wounds were covered by the epidermis from a donor site. The surgical areas were bandaged for 7-10 days before the first dressing change.

RESULTS

25 patients (mean [SD] age, 26.4 [18.8] years; 16 [64%] men) underwent wounds reconstructive operations due to scar resection were reviewed. Wound location of 9 (22%), 8 (19.5%), 9 (22%), 7 (17.1%) and 8 (19.5%) cases were reconstructed in axillary, hand and wrist, popliteal fossa, elbow and neck, respectively. 39 sites of transplanted tissues survived well, and 2 sites were cured after two weeks of dressing changes. Except the analysis of injury causes, nutritional status, wound area and hospital days, patients with scar deformities in joint areas achieved satisfactory function by assessing the Vancouver Burn Skin Score and the Barthel Index Scale Scores after 12-month follow-up.

CONCLUSIONS

Combining autologous scar-related tissue with skin grafting provided a novel method for treating large areas of burn scars with better functional outcomes.